I only did a basic BGP lab on my last blog post. This is the continuation of my BGP lab, but this time I manipulated its various attributes. I usually don't configure or troubleshoot BGP most of the time in our production network. It's one of those routing protocols that once you've setup correctly, you virtually don't have to deal with it again (unless there's an outage).
ISP(config)#interface loopback0
ISP(config-if)#
*Jan 3 09:41:48.663: %LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback0, changed state to up
ISP(config-if)#ip address 192.168.100.1 255.255.255.0
ISP(config-if)#interface s0/0/0
ISP(config-if)#ip address 192.168.1.5 255.255.255.252
ISP(config-if)#clock rate 128000
ISP(config-if)#no shutdown
ISP(config-if)#
*Jan 3 09:42:29.367: %LINK-3-UPDOWN: Interface Serial0/0/0, changed state to down
ISP(config-if)#interface s0/0/1
ISP(config-if)#ip address 192.168.1.1 255.255.255.252
ISP(config-if)#no shutdown
ISP(config-if)#
*Jan 3 09:42:53.707: %LINK-3-UPDOWN: Interface Serial0/0/1, changed state to down
SanJose1(config)#interface loopback0
SanJose1(config-if)#
*Jan 3 08:25:31.687: %LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback0, changed state to up
SanJose1(config-if)#ip address 172.16.64.1 255.255.255.0
SanJose1(config-if)#interface s0/0/0
SanJose1(config-if)#ip address 192.168.1.6 255.255.255.252
SanJose1(config-if)#no shutdown
SanJose1(config-if)#
*Jan 3 08:26:03.563: %LINK-3-UPDOWN: Interface Serial0/0/0, changed state to up
*Jan 3 08:26:04.563: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/0, changed state to up
SanJose1(config-if)#do ping 192.168.1.5
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.5, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms
SanJose1(config-if)#interface s0/0/1
SanJose1(config-if)#ip address 172.16.1.1 255.255.255.0
SanJose1(config-if)#clock rate 128000
SanJose1(config-if)#no shutdown
SanJose1(config-if)#
*Jan 3 08:26:32.963: %LINK-3-UPDOWN: Interface Serial0/0/1, changed state to up
*Jan 3 08:26:33.963: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/1, changed state to up
SanJose2(config)#interface loopback0
SanJose2(config-if)#
*Jan 3 09:04:26.239: %LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback0, changed state to up
SanJose2(config-if)#ip address 172.16.32.1 255.255.255.0
SanJose2(config-if)#interface s0/0/0
SanJose2(config-if)#ip address 192.168.1.2 255.255.255.252
SanJose2(config-if)#clock rate 128000
SanJose2(config-if)#no shutdown
SanJose2(config-if)#
*Jan 3 09:05:07.603: %LINK-3-UPDOWN: Interface Serial0/0/0, changed state to up
*Jan 3 09:05:08.603: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/0, changed state to up
SanJose2(config-if)#do ping 192.168.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms
SanJose2(config-if)#interface s0/0/1
SanJose2(config-if)#ip address 172.16.1.2 255.255.255.0
SanJose2(config-if)#no shutdown
SanJose2(config-if)#do ping 172.16.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
SanJose1(config)#router eigrp 64512
SanJose1(config-router)#no auto-summary
SanJose1(config-router)#network 172.16.0.0
SanJose2(config)#router eigrp 64512
SanJose2(config-router)#no auto-summary
SanJose2(config-router)#network 172.16.0.0
SanJose2(config-router)#
*Jan 3 09:07:14.023: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 64512: Neighbor 172.16.1.1 (Serial0/0/1) is up:
new adjacency
SanJose2(config-router)#end
SanJose2#
*Jan 3 09:07:27.687: %SYS-5-CONFIG_I: Configured from console by console
SanJose2#show ip eigrp neighbors
IP-EIGRP neighbors for process 64512
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.1.1 Se0/0/1 12 00:00:20 12 300 0 3
SanJose1(config)#router bgp 64512
SanJose1(config-router)#neighbor 172.16.32.1 remote-as 64512 // SAME ASN FOR IBGP PEER
SanJose1(config-router)#neighbor 172.16.32.1 update-source ?
Async Async interface
Auto-Template Auto-Template interface
BVI Bridge-Group Virtual Interface
CDMA-Ix CDMA Ix interface
CTunnel CTunnel interface
Dialer Dialer interface
FastEthernet FastEthernet IEEE 802.3
Lex Lex interface
Loopback Loopback interface
MFR Multilink Frame Relay bundle interface
Multilink Multilink-group interface
Null Null interface
SSLVPN-VIF SSLVPN Virtual Interface
Serial Serial
Tunnel Tunnel interface
Vif PGM Multicast Host interface
Virtual-Dot11Radio Virtual dot11 interface
Virtual-PPP Virtual PPP interface
Virtual-Template Virtual Template interface
Virtual-TokenRing Virtual TokenRing
vmi Virtual Multipoint Interface
SanJose1(config-router)#neighbor 172.16.32.1 update-source loopback0 // USE LOOPBACK 0 AS THE SOURCE IP ADDRESS FOR ALL BGP MESSAGES IF MULTIPLE PATHS EXIST TO THE BGP NEIGHBOR
SanJose2(config)#router bgp 64512
SanJose2(config-router)#neighbor 172.16.64.1 remote-as 64512
SanJose2(config-router)#neighbor 172.16.64.1 update-source loopback0
SanJose2(config-router)#
*Jan 3 09:11:22.983: %BGP-5-ADJCHANGE: neighbor 172.16.64.1 Up
SanJose2#show ip bgp neighbors
BGP neighbor is 172.16.64.1, remote AS 64512, internal link
BGP version 4, remote router ID 172.16.64.1
BGP state = Established, up for 00:00:23
Last read 00:00:23, last write 00:00:23, hold time is 180, keepalive interval is 60 seconds
Neighbor capabilities:
Route refresh: advertised and received(new)
New ASN Capability: advertised and received
Address family IPv4 Unicast: advertised and received
Message statistics:
InQ depth is 0
OutQ depth is 0
Sent Rcvd
Opens: 1 1
Notifications: 0 0
Updates: 0 0
Keepalives: 1 1
Route Refresh: 0 0
Total: 2 2
Default minimum time between advertisement runs is 0 seconds
For address family: IPv4 Unicast
BGP table version 1, neighbor version 0/0
Output queue size : 0
Index 1, Offset 0, Mask 0x2
1 update-group member
Sent Rcvd
Prefix activity: ---- ----
Prefixes Current: 0 0
Prefixes Total: 0 0
Implicit Withdraw: 0 0
Explicit Withdraw: 0 0
Used as bestpath: n/a 0
Used as multipath: n/a 0
Outbound Inbound
Local Policy Denied Prefixes: -------- -------
Total: 0 0
Number of NLRIs in the update sent: max 0, min 0
Address tracking is enabled, the RIB does have a route to 172.16.64.1
Connections established 1; dropped 0
Last reset never
Transport(tcp) path-mtu-discovery is enabled
Connection state is ESTAB, I/O status: 1, unread input bytes: 0
Connection is ECN Disabled, Mininum incoming TTL 0, Outgoing TTL 255
Local host: 172.16.32.1, Local port: 179
Foreign host: 172.16.64.1, Foreign port: 44852
Connection tableid (VRF): 0
Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes)
Event Timers (current time is 0x10DF68):
Timer Starts Wakeups Next
Retrans 3 0 0x0
TimeWait 0 0 0x0
AckHold 2 1 0x0
SendWnd 0 0 0x0
KeepAlive 0 0 0x0
GiveUp 0 0 0x0
PmtuAger 0 0 0x0
DeadWait 0 0 0x0
Linger 0 0 0x0
ProcessQ 0 0 0x0
iss: 3034847281 snduna: 3034847354 sndnxt: 3034847354 sndwnd: 16312
irs: 4118955732 rcvnxt: 4118955805 rcvwnd: 16312 delrcvwnd: 72
SRTT: 99 ms, RTTO: 1539 ms, RTV: 1440 ms, KRTT: 0 ms
minRTT: 8 ms, maxRTT: 300 ms, ACK hold: 200 ms
Status Flags: passive open, gen tcbs
Option Flags: nagle, path mtu capable
IP Precedence value : 6
Datagrams (max data segment is 536 bytes):
Rcvd: 5 (out of order: 0), with data: 2, total data bytes: 72
Sent: 4 (retransmit: 0, fastretransmit: 0, partialack: 0, Second Congestion: 0), with data: 2, total
data bytes: 72
Packets received in fast path: 0, fast processed: 0, slow path: 0
fast lock acquisition failures: 0, slow path: 0
ISP(config)#router bgp 200
ISP(config-router)#neighbor 192.168.1.6 remote-as 64512 // DIFFERENT ASN FOR EBGP PEER
ISP(config-router)#neighbor 192.168.1.2 remote-as 64512 // NO NEED FOR update-source SINCE THERE'S ONLY ONE PATH AVAILABLE
EXIST TO BGP PEER
ISP(config-router)#network 192.168.100.0
SanJose1(config)#ip route 172.16.0.0 255.255.0.0 null0
SanJose1(config)#router bgp 64512
SanJose1(config-router)#neighbor 192.168.1.5 remote-as 200
SanJose1(config-router)#network 172.16.0.0
SanJose1(config-router)#
*Jan 3 08:37:41.055: %BGP-5-ADJCHANGE: neighbor 192.168.1.5 Up
SanJose1#show ip bgp neighbors
BGP neighbor is 172.16.32.1, remote AS 64512, internal link
BGP version 4, remote router ID 172.16.32.1
BGP state = Established, up for 00:03:54
Last read 00:00:57, last write 00:00:17, hold time is 180, keepalive interval is 60 seconds
Neighbor capabilities:
Route refresh: advertised and received(new)
New ASN Capability: advertised and received
Address family IPv4 Unicast: advertised and received
Message statistics:
InQ depth is 0
OutQ depth is 0
Sent Rcvd
Opens: 1 1
Notifications: 0 0
Updates: 1 0
Keepalives: 4 4
Route Refresh: 0 0
Total: 6 5
Default minimum time between advertisement runs is 0 seconds
For address family: IPv4 Unicast
BGP table version 2, neighbor version 2/0
Output queue size : 0
Index 1, Offset 0, Mask 0x2
1 update-group member
Sent Rcvd
Prefix activity: ---- ----
Prefixes Current: 1 0
Prefixes Total: 1 0
Implicit Withdraw: 0 0
Explicit Withdraw: 0 0
Used as bestpath: n/a 0
Used as multipath: n/a 0
Outbound Inbound
Local Policy Denied Prefixes: -------- -------
Total: 0 0
Number of NLRIs in the update sent: max 1, min 1
Address tracking is enabled, the RIB does have a route to 172.16.32.1
Connections established 1; dropped 0
Last reset never
Transport(tcp) path-mtu-discovery is enabled
Connection state is ESTAB, I/O status: 1, unread input bytes: 0
Connection is ECN Disabled, Mininum incoming TTL 0, Outgoing TTL 255
Local host: 172.16.64.1, Local port: 44852
Foreign host: 172.16.32.1, Foreign port: 179
Connection tableid (VRF): 0
Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes)
Event Timers (current time is 0x143C14):
Timer Starts Wakeups Next
Retrans 7 0 0x0
TimeWait 0 0 0x0
AckHold 6 2 0x0
SendWnd 0 0 0x0
KeepAlive 0 0 0x0
GiveUp 0 0 0x0
PmtuAger 1 0 0x19B684
DeadWait 0 0 0x0
Linger 0 0 0x0
ProcessQ 0 0 0x0
iss: 4118955732 snduna: 4118955916 sndnxt: 4118955916 sndwnd: 16201
irs: 3034847281 rcvnxt: 3034847430 rcvwnd: 16236 delrcvwnd: 148
SRTT: 182 ms, RTTO: 1073 ms, RTV: 891 ms, KRTT: 0 ms
minRTT: 8 ms, maxRTT: 300 ms, ACK hold: 200 ms
Status Flags: active open
Option Flags: nagle, path mtu capable
IP Precedence value : 6
Datagrams (max data segment is 536 bytes):
Rcvd: 12 (out of order: 0), with data: 6, total data bytes: 148
Sent: 10 (retransmit: 0, fastretransmit: 0, partialack: 0, Second Congestion: 0), with data: 6, total
data bytes: 183
Packets received in fast path: 0, fast processed: 0, slow path: 0
fast lock acquisition failures: 0, slow path: 0
BGP neighbor is 192.168.1.5, remote AS 200, external link
BGP version 4, remote router ID 192.168.100.1
BGP state = Established, up for 00:00:27
Last read 00:00:27, last write 00:00:27, hold time is 180, keepalive interval is 60 seconds
Neighbor capabilities:
Route refresh: advertised and received(new)
New ASN Capability: advertised and received
Address family IPv4 Unicast: advertised and received
Message statistics:
InQ depth is 0
OutQ depth is 0
Sent Rcvd
Opens: 1 1
Notifications: 0 0
Updates: 1 0
Keepalives: 2 1
Route Refresh: 0 0
Total: 4 2
Default minimum time between advertisement runs is 30 seconds
For address family: IPv4 Unicast
BGP table version 3, neighbor version 3/0
Output queue size : 0
Index 2, Offset 0, Mask 0x4
2 update-group member
Sent Rcvd
Prefix activity: ---- ----
Prefixes Current: 1 1
Prefixes Total: 1 1
Implicit Withdraw: 0 0
Explicit Withdraw: 0 0
Used as bestpath: n/a 0
Used as multipath: n/a 0
Outbound Inbound
Local Policy Denied Prefixes: -------- -------
Bestpath from this peer: 1 n/a
Total: 1 0
Number of NLRIs in the update sent: max 1, min 1
Address tracking is enabled, the RIB does have a route to 192.168.1.5
Connections established 1; dropped 0
Last reset never
Transport(tcp) path-mtu-discovery is enabled
Connection state is ESTAB, I/O status: 1, unread input bytes: 0
Connection is ECN Disabled, Mininum incoming TTL 0, Outgoing TTL 1
Local host: 192.168.1.6, Local port: 48273
Foreign host: 192.168.1.5, Foreign port: 179
Connection tableid (VRF): 0
Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes)
Event Timers (current time is 0x147674):
Timer Starts Wakeups Next
Retrans 3 0 0x0
TimeWait 0 0 0x0
AckHold 3 1 0x0
SendWnd 0 0 0x0
KeepAlive 0 0 0x0
GiveUp 0 0 0x0
PmtuAger 1 0 0x1D0754
DeadWait 0 0 0x0
Linger 0 0 0x0
ProcessQ 0 0 0x0
iss: 1364026979 snduna: 1364027124 sndnxt: 1364027124 sndwnd: 16240
irs: 1747390620 rcvnxt: 1747390766 rcvwnd: 16239 delrcvwnd: 145
SRTT: 99 ms, RTTO: 1539 ms, RTV: 1440 ms, KRTT: 0 ms
minRTT: 8 ms, maxRTT: 300 ms, ACK hold: 200 ms
Status Flags: active open
Option Flags: nagle, path mtu capable
IP Precedence value : 6
Datagrams (max data segment is 1460 bytes):
Rcvd: 6 (out of order: 0), with data: 4, total data bytes: 145
Sent: 7 (retransmit: 0, fastretransmit: 0, partialack: 0, Second Congestion: 0), with data: 4, total
data bytes: 144
Packets received in fast path: 0, fast processed: 0, slow path: 0
fast lock acquisition failures: 0, slow path: 0
SanJose1#show ip bgp summary
BGP router identifier 172.16.64.1, local AS number 64512
BGP table version is 3, main routing table version 3
2 network entries using 264 bytes of memory
2 path entries using 104 bytes of memory
3/2 BGP path/bestpath attribute entries using 504 bytes of memory
1 BGP AS-PATH entries using 24 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
Bitfield cache entries: current 2 (at peak 2) using 64 bytes of memory
BGP using 960 total bytes of memory
BGP activity 2/0 prefixes, 2/0 paths, scan interval 60 secs
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
172.16.32.1 4 64512 7 7 3 0 0 00:05:06 0
192.168.1.5 4 200 4 5 3 0 0 00:01:28 1
SanJose2(config)#ip route 172.16.0.0 255.255.0.0 null0
SanJose2(config)#router bgp 64512
SanJose2(config-router)#neighbor 192.168.1.1 remote-as 200
SanJose2(config-router)#network 172.16.0.0
SanJose2(config-router)#
*Jan 3 09:17:21.507: %BGP-5-ADJCHANGE: neighbor 192.168.1.1 Up
SanJose2#show ip bgp summary
BGP router identifier 172.16.32.1, local AS number 64512
BGP table version is 5, main routing table version 5
2 network entries using 264 bytes of memory
4 path entries using 208 bytes of memory
5/2 BGP path/bestpath attribute entries using 840 bytes of memory
1 BGP AS-PATH entries using 24 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
Bitfield cache entries: current 2 (at peak 2) using 64 bytes of memory
BGP using 1400 total bytes of memory
BGP activity 2/0 prefixes, 4/0 paths, scan interval 60 secs
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
172.16.64.1 4 64512 9 9 5 0 0 00:06:24 2
192.168.1.1 4 200 5 4 4 0 0 00:00:25 1
ISP#clear ip bgp *
ISP#
*Jan 3 09:59:21.235: %BGP-5-ADJCHANGE: neighbor 192.168.1.2 Down User reset
*Jan 3 09:59:21.239: %BGP-5-ADJCHANGE: neighbor 192.168.1.6 Down User reset
*Jan 3 09:59:25.547: %BGP-5-ADJCHANGE: neighbor 192.168.1.6 Up
*Jan 3 09:59:34.763: %BGP-5-ADJCHANGE: neighbor 192.168.1.2 Up
ISP#ping 172.16.64.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.64.1, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
ISP#ping 172.16.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
ISP#ping 172.16.32.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.32.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
ISP#ping 172.16.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
ISP#show ip bgp
BGP table version is 3, local router ID is 192.168.100.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 172.16.0.0 192.168.1.2 0 0 64512 i // SanJose2 WAS CHOSEN AS NEXT HOP DUE TO LOWER ROUTER ID 172.16.32.1 VS SanJose1 ROUTER ID 172.16.64.1 IF ALL PATH ATTRIBUTES ARE EQUAL
* 192.168.1.6 0 0 64512 i
*> 192.168.100.0 0.0.0.0 0 32768 i
ISP#ping 172.16.1.1 source 192.168.100.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
Packet sent with a source address of 192.168.100.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/21/24 ms
ISP#ping 172.16.32.1 source 192.168.100.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.32.1, timeout is 2 seconds:
Packet sent with a source address of 192.168.100.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
ISP#ping 172.16.1.2 source 192.168.100.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:
Packet sent with a source address of 192.168.100.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
ISP#ping 172.16.64.1 source 192.168.100.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.64.1, timeout is 2 seconds:
Packet sent with a source address of 192.168.100.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/21/24 ms
ISP(config)#router bgp 200
ISP(config-router)#network 192.168.1.0 mask 255.255.255.252
ISP(config-router)#network 192.168.1.4 mask 255.255.255.252
ISP(config-router)#do show ip bgp
BGP table version is 5, local router ID is 192.168.100.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 172.16.0.0 192.168.1.2 0 0 64512 i
* 192.168.1.6 0 0 64512 i
*> 192.168.1.0/30 0.0.0.0 0 32768 i
*> 192.168.1.4/30 0.0.0.0 0 32768 i
*> 192.168.100.0 0.0.0.0 0 32768 i
SanJose1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 4 subnets, 2 masks
D 172.16.32.0/24 [90/2297856] via 172.16.1.2, 00:20:13, Serial0/0/1
S 172.16.0.0/16 is directly connected, Null0
C 172.16.1.0/24 is directly connected, Serial0/0/1
C 172.16.64.0/24 is directly connected, Loopback0
192.168.1.0/30 is subnetted, 2 subnets
B 192.168.1.0 [20/0] via 192.168.1.5, 00:00:55
C 192.168.1.4 is directly connected, Serial0/0/0
B 192.168.100.0/24 [20/0] via 192.168.1.5, 00:07:59
SanJose2#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 4 subnets, 2 masks
C 172.16.32.0/24 is directly connected, Loopback0
S 172.16.0.0/16 is directly connected, Null0
C 172.16.1.0/24 is directly connected, Serial0/0/1
D 172.16.64.0/24 [90/2297856] via 172.16.1.1, 00:20:49, Serial0/0/1
192.168.1.0/30 is subnetted, 2 subnets
C 192.168.1.0 is directly connected, Serial0/0/0
B 192.168.1.4 [20/0] via 192.168.1.1, 00:01:00
B 192.168.100.0/24 [20/0] via 192.168.1.1, 00:08:35
SanJose2#show ip bgp
BGP table version is 10, local router ID is 172.16.32.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 172.16.0.0 0.0.0.0 0 32768 i
* i 172.16.64.1 0 100 0 i
r i192.168.1.0/30 192.168.1.5 0 100 0 200 i
r> 192.168.1.1 0 0 200 i
* i192.168.1.4/30 192.168.1.5 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
* i192.168.100.0 192.168.1.5 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
SanJose2(config)#router bgp 64512
SanJose2(config-router)#neighbor 172.16.64.1 ?
activate Enable the Address Family for this Neighbor
advertise-map specify route-map for conditional advertisement
advertisement-interval Minimum interval between sending BGP routing updates
allowas-in Accept as-path with my AS present in it
capability Advertise capability to the peer
default-originate Originate default route to this neighbor
description Neighbor specific description
disable-connected-check one-hop away EBGP peer using loopback address
distribute-list Filter updates to/from this neighbor
dmzlink-bw Propagate the DMZ link bandwidth
ebgp-multihop Allow EBGP neighbors not on directly connected
networks
fall-over session fall on peer route lost
filter-list Establish BGP filters
inherit Inherit a template
local-as Specify a local-as number
maximum-prefix Maximum number of prefixes accepted from this peer
next-hop-self Disable the next hop calculation for this neighbor
next-hop-unchanged Propagate next hop unchanged for iBGP paths to this
neighbor
password Set a password
peer-group Member of the peer-group
prefix-list Filter updates to/from this neighbor
remote-as Specify a BGP neighbor
remove-private-as Remove private AS number from outbound updates
route-map Apply route map to neighbor
route-reflector-client Configure a neighbor as Route Reflector client
send-community Send Community attribute to this neighbor
send-label Send NLRI + MPLS Label to this peer
shutdown Administratively shut down this neighbor
soft-reconfiguration Per neighbor soft reconfiguration
timers BGP per neighbor timers
translate-update Translate Update to MBGP format
transport Transport options
ttl-security BGP ttl security check
unsuppress-map Route-map to selectively unsuppress suppressed
routes
update-source Source of routing updates
version Set the BGP version to match a neighbor
weight Set default weight for routes from this neighbor
SanJose2(config-router)#neighbor 172.16.64.1 next-hop-self // SET THE IP ADDRESS OF THE BORDER ROUTER IN DIFFERENT ASN; NOT MODIFIED FOR IBGP PEER
SanJose1(config)#router bgp 64512
SanJose1(config-router)#neighbor 172.16.32.1 next-hop-self
SanJose1#clear ip bgp 172.16.32.1
SanJose1#
*Jan 3 08:54:54.947: %BGP-5-ADJCHANGE: neighbor 172.16.32.1 Down User reset
*Jan 3 08:54:55.311: %BGP-5-ADJCHANGE: neighbor 172.16.32.1 Up
SanJose2#show ip bgp
BGP table version is 10, local router ID is 172.16.32.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.64.1 0 100 0 i
*> 0.0.0.0 0 32768 i
r i192.168.1.0/30 172.16.64.1 0 100 0 200 i
r> 192.168.1.1 0 0 200 i
* i192.168.1.4/30 172.16.64.1 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
* i192.168.100.0 172.16.64.1 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
SanJose1#show ip bgp
BGP table version is 8, local router ID is 172.16.64.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.32.1 0 100 0 i
*> 0.0.0.0 0 32768 i
* i192.168.1.0/30 172.16.32.1 0 100 0 200 i
*> 192.168.1.5 0 0 200 i
r i192.168.1.4/30 172.16.32.1 0 100 0 200 i
r> 192.168.1.5 0 0 200 i
* i192.168.100.0 172.16.32.1 0 100 0 200 i
*> 192.168.1.5 0 0 200 i
SanJose2#show ip bgp
BGP table version is 10, local router ID is 172.16.32.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.64.1 0 100 0 i
*> 0.0.0.0 0 32768 i
r i192.168.1.0/30 172.16.64.1 0 100 0 200 i
r> 192.168.1.1 0 0 200 i
* i192.168.1.4/30 172.16.64.1 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
* i192.168.100.0 172.16.64.1 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
SanJose1(config)#route-map PRIMARY_T1_IN permit 10
SanJose1(config-route-map)#set ?
as-path Prepend string for a BGP AS-path attribute
automatic-tag Automatically compute TAG value
clns OSI summary address
comm-list set BGP community list (for deletion)
community BGP community attribute
dampening Set BGP route flap dampening parameters
default Set default information
extcomm-list Set BGP/VPN extended community list (for deletion)
extcommunity BGP extended community attribute
global Set to global routing table
interface Output interface
ip IP specific information
ipv6 IPv6 specific information
level Where to import route
local-preference BGP local preference path attribute
metric Metric value for destination routing protocol
metric-type Type of metric for destination routing protocol
mpls-label Set MPLS label for prefix
nlri BGP NLRI type
origin BGP origin code
tag Tag value for destination routing protocol
traffic-index BGP traffic classification number for accounting
vrf Define VRF name
weight BGP weight for routing table
SanJose1(config-route-map)#set local-preference ?
<0-4294967295> Preference value
<cr>
SanJose1(config-route-map)#set local-preference 150 // ADVERTISED BETWEEN IBGP PEER FOR OUTBOUND TRAFFIC; DEFAULT VALUE IS 100
SanJose1(config-route-map)#exit
SanJose1(config)#router bgp 64512
SanJose1(config-router)#neighbor 192.168.1.5 route-map PRIMARY_T1_IN in
SanJose2(config)#route-map SECONDARY_T1_IN permit 10
SanJose2(config-route-map)#set local-preference 125
SanJose2(config-route-map)#exit
SanJose2(config)#router bgp 64512
SanJose2(config-router)#neighbor 192.168.1.1 route-map SECONDARY_T1_IN in
SanJose1#clear ip bgp * soft
SanJose2#clear ip bgp * soft
SanJose1#show ip bgp
BGP table version is 11, local router ID is 172.16.64.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.32.1 0 100 0 i
*> 0.0.0.0 0 32768 i
*> 192.168.1.0/30 192.168.1.5 0 150 0 200 i
r> 192.168.1.4/30 192.168.1.5 0 150 0 200 i
*> 192.168.100.0 192.168.1.5 0 150 0 200 i
SanJose2#show ip bgp
BGP table version is 16, local router ID is 172.16.32.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.64.1 0 100 0 i
*> 0.0.0.0 0 32768 i
r>i192.168.1.0/30 172.16.64.1 0 150 0 200 i
r 192.168.1.1 0 125 0 200 i
*>i192.168.1.4/30 172.16.64.1 0 150 0 200 i
* 192.168.1.1 0 125 0 200 i
*>i192.168.100.0 172.16.64.1 0 150 0 200 i
* 192.168.1.1 0 125 0 200 i
ISP#show ip bgp
BGP table version is 5, local router ID is 192.168.100.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 172.16.0.0 192.168.1.2 0 0 64512 i
* 192.168.1.6 0 0 64512 i
*> 192.168.1.0/30 0.0.0.0 0 32768 i
*> 192.168.1.4/30 0.0.0.0 0 32768 i
*> 192.168.100.0 0.0.0.0 0 32768 i
SanJose2#ping
Protocol [ip]:
Target IP address: 192.168.100.1
Repeat count [5]:
Datagram size [100]:
Timeout in seconds [2]:
Extended commands [n]: y
Source address or interface: 172.16.32.1
Type of service [0]:
Set DF bit in IP header? [no]:
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]: record // RECORDS PACKET'S HOP/IP ADDRESS
Number of hops [ 9 ]:
Loose, Strict, Record, Timestamp, Verbose[RV]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.100.1, timeout is 2 seconds:
Packet sent with a source address of 172.16.32.1
Packet has IP options: Total option bytes= 39, padded length=40
Record route: <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
Reply to request 0 (20 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2) SanJose2 S0/0/1
(192.168.1.6) SanJose1 S0/0/0
(192.168.100.1) ISP LOOPBACK0
(192.168.1.1) ISP S0/0/0
(172.16.32.1) <*> SanJose2 LOOPBACK2 // RETURN TRAFFIC PREFERS SanJose2
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 1 (20 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 2 (24 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 3 (20 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 4 (20 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/20/24 ms
SanJose1(config)#route-map PRIMARY_T1_MED_OUT permit 10
SanJose1(config-route-map)#set ?
as-path Prepend string for a BGP AS-path attribute
automatic-tag Automatically compute TAG value
clns OSI summary address
comm-list set BGP community list (for deletion)
community BGP community attribute
dampening Set BGP route flap dampening parameters
default Set default information
extcomm-list Set BGP/VPN extended community list (for deletion)
extcommunity BGP extended community attribute
global Set to global routing table
interface Output interface
ip IP specific information
ipv6 IPv6 specific information
level Where to import route
local-preference BGP local preference path attribute
metric Metric value for destination routing protocol
metric-type Type of metric for destination routing protocol
mpls-label Set MPLS label for prefix
nlri BGP NLRI type
origin BGP origin code
tag Tag value for destination routing protocol
traffic-index BGP traffic classification number for accounting
vrf Define VRF name
weight BGP weight for routing table
SanJose1(config-route-map)#set metric ?
+/-<metric> Add or subtract metric
<0-4294967295> Metric value or Bandwidth in Kbits per second
SanJose1(config-route-map)#set metric 50 // BGP MED (LOWER IS BETTER); ADVERTISED TO EBGP PEER FOR INBOUND TRAFFIC
SanJose1(config-route-map)#exit
SanJose1(config)#router bgp 64512
SanJose1(config-router)#neighbor 192.168.1.5 route-map PRIMARY_T1_MED_OUT ?
in Apply map to incoming routes
out Apply map to outbound routes
SanJose1(config-router)#neighbor 192.168.1.5 route-map PRIMARY_T1_MED_OUT out // POLICY TO FORCE ISP ROUTER TO RETURN TRAFFIC VIA SanJose1
SanJose2(config)#route-map SECONDARY_T1_MED_OUT permit 10
SanJose2(config-route-map)#set metric 75
SanJose2(config-route-map)#exit
SanJose2(config)#router bgp 64512
SanJose2(config-router)#neighbor 192.168.1.1 route-map SECONDARY_T1_MED_OUT out
SanJose1#clear ip bgp * soft
SanJose2#clear ip bgp * soft
ISP#show ip bgp
BGP table version is 6, local router ID is 192.168.100.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* 172.16.0.0 192.168.1.2 75 0 64512 i // SanJose2 HOP
*> 192.168.1.6 50 0 64512 i // SanJose1 HOP
*> 192.168.1.0/30 0.0.0.0 0 32768 i
*> 192.168.1.4/30 0.0.0.0 0 32768 i
*> 192.168.100.0 0.0.0.0 0 32768 i
SanJose1#show ip bgp // MED REFLECTED ON ISP/UPSTREAM ROUTER
BGP table version is 11, local router ID is 172.16.64.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.32.1 0 100 0 i
*> 0.0.0.0 0 32768 i
*> 192.168.1.0/30 192.168.1.5 0 150 0 200 i
r> 192.168.1.4/30 192.168.1.5 0 150 0 200 i
*> 192.168.100.0 192.168.1.5 0 150 0 200 i
SanJose2#ping
Protocol [ip]:
Target IP address: 192.168.100.1
Repeat count [5]:
Datagram size [100]:
Timeout in seconds [2]:
Extended commands [n]: y
Source address or interface: 172.16.32.1
Type of service [0]:
Set DF bit in IP header? [no]:
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]: record
Number of hops [ 9 ]:
Loose, Strict, Record, Timestamp, Verbose[RV]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.100.1, timeout is 2 seconds:
Packet sent with a source address of 172.16.32.1
Packet has IP options: Total option bytes= 39, padded length=40
Record route: <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
Reply to request 0 (48 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1) ISP LOOPBACK0 IP ADDRESS
(192.168.1.5) ISP S0/0/0
(172.16.1.1) SanJose1 S0/0/1 // ISP NOW PREFERS SanJose1 FOR RETURN TRAFFIC
(172.16.32.1) <*> SanJose2 LOOPBACK0 IP ADDRESS
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 1 (28 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.5)
(172.16.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 2 (32 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.5)
(172.16.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 3 (28 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.5)
(172.16.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 4 (32 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.5)
(172.16.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/33/48 ms
SanJose1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 4 subnets, 2 masks
D 172.16.32.0/24 [90/2297856] via 172.16.1.2, 00:58:53, Serial0/0/1
S 172.16.0.0/16 is directly connected, Null0
C 172.16.1.0/24 is directly connected, Serial0/0/1
C 172.16.64.0/24 is directly connected, Loopback0
192.168.1.0/30 is subnetted, 2 subnets
B 192.168.1.0 [20/0] via 192.168.1.5, 00:39:35
C 192.168.1.4 is directly connected, Serial0/0/0
B 192.168.100.0/24 [20/0] via 192.168.1.5, 00:46:39
SanJose1(config)#ip default-network 192.168.100.0
SanJose1(config)#end
SanJose1#show ip route
*Jan 3 09:29:16.403: %SYS-5-CONFIG_I: Configured from console by console
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is 192.168.1.5 to network 192.168.100.0
172.16.0.0/16 is variably subnetted, 4 subnets, 2 masks
D 172.16.32.0/24 [90/2297856] via 172.16.1.2, 00:59:23, Serial0/0/1
S 172.16.0.0/16 is directly connected, Null0
C 172.16.1.0/24 is directly connected, Serial0/0/1
C 172.16.64.0/24 is directly connected, Loopback0
192.168.1.0/30 is subnetted, 2 subnets
B 192.168.1.0 [20/0] via 192.168.1.5, 00:40:04
C 192.168.1.4 is directly connected, Serial0/0/0
B* 192.168.100.0/24 [20/0] via 192.168.1.5, 00:47:09
ISP#tclsh
ISP(tcl)#foreach address {
+>192.168.100.1
+>172.16.64.1
+>172.16.32.1
+>192.168.1.1
+>192.168.1.2
+>192.168.1.5
+>192.168.1.6
+>172.16.1.1
+>172.16.1.2
+>} {
+>ping $address }
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.100.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/4 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.64.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/13/16 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.32.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.5, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/28 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.6, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
ISP(config-if)#
*Jan 3 09:41:48.663: %LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback0, changed state to up
ISP(config-if)#ip address 192.168.100.1 255.255.255.0
ISP(config-if)#interface s0/0/0
ISP(config-if)#ip address 192.168.1.5 255.255.255.252
ISP(config-if)#clock rate 128000
ISP(config-if)#no shutdown
ISP(config-if)#
*Jan 3 09:42:29.367: %LINK-3-UPDOWN: Interface Serial0/0/0, changed state to down
ISP(config-if)#interface s0/0/1
ISP(config-if)#ip address 192.168.1.1 255.255.255.252
ISP(config-if)#no shutdown
ISP(config-if)#
*Jan 3 09:42:53.707: %LINK-3-UPDOWN: Interface Serial0/0/1, changed state to down
SanJose1(config)#interface loopback0
SanJose1(config-if)#
*Jan 3 08:25:31.687: %LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback0, changed state to up
SanJose1(config-if)#ip address 172.16.64.1 255.255.255.0
SanJose1(config-if)#interface s0/0/0
SanJose1(config-if)#ip address 192.168.1.6 255.255.255.252
SanJose1(config-if)#no shutdown
SanJose1(config-if)#
*Jan 3 08:26:03.563: %LINK-3-UPDOWN: Interface Serial0/0/0, changed state to up
*Jan 3 08:26:04.563: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/0, changed state to up
SanJose1(config-if)#do ping 192.168.1.5
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.5, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms
SanJose1(config-if)#interface s0/0/1
SanJose1(config-if)#ip address 172.16.1.1 255.255.255.0
SanJose1(config-if)#clock rate 128000
SanJose1(config-if)#no shutdown
SanJose1(config-if)#
*Jan 3 08:26:32.963: %LINK-3-UPDOWN: Interface Serial0/0/1, changed state to up
*Jan 3 08:26:33.963: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/1, changed state to up
SanJose2(config)#interface loopback0
SanJose2(config-if)#
*Jan 3 09:04:26.239: %LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback0, changed state to up
SanJose2(config-if)#ip address 172.16.32.1 255.255.255.0
SanJose2(config-if)#interface s0/0/0
SanJose2(config-if)#ip address 192.168.1.2 255.255.255.252
SanJose2(config-if)#clock rate 128000
SanJose2(config-if)#no shutdown
SanJose2(config-if)#
*Jan 3 09:05:07.603: %LINK-3-UPDOWN: Interface Serial0/0/0, changed state to up
*Jan 3 09:05:08.603: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/0, changed state to up
SanJose2(config-if)#do ping 192.168.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms
SanJose2(config-if)#interface s0/0/1
SanJose2(config-if)#ip address 172.16.1.2 255.255.255.0
SanJose2(config-if)#no shutdown
SanJose2(config-if)#do ping 172.16.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
SanJose1(config)#router eigrp 64512
SanJose1(config-router)#no auto-summary
SanJose1(config-router)#network 172.16.0.0
SanJose2(config)#router eigrp 64512
SanJose2(config-router)#no auto-summary
SanJose2(config-router)#network 172.16.0.0
SanJose2(config-router)#
*Jan 3 09:07:14.023: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 64512: Neighbor 172.16.1.1 (Serial0/0/1) is up:
new adjacency
SanJose2(config-router)#end
SanJose2#
*Jan 3 09:07:27.687: %SYS-5-CONFIG_I: Configured from console by console
SanJose2#show ip eigrp neighbors
IP-EIGRP neighbors for process 64512
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.1.1 Se0/0/1 12 00:00:20 12 300 0 3
SanJose1(config)#router bgp 64512
SanJose1(config-router)#neighbor 172.16.32.1 remote-as 64512 // SAME ASN FOR IBGP PEER
SanJose1(config-router)#neighbor 172.16.32.1 update-source ?
Async Async interface
Auto-Template Auto-Template interface
BVI Bridge-Group Virtual Interface
CDMA-Ix CDMA Ix interface
CTunnel CTunnel interface
Dialer Dialer interface
FastEthernet FastEthernet IEEE 802.3
Lex Lex interface
Loopback Loopback interface
MFR Multilink Frame Relay bundle interface
Multilink Multilink-group interface
Null Null interface
SSLVPN-VIF SSLVPN Virtual Interface
Serial Serial
Tunnel Tunnel interface
Vif PGM Multicast Host interface
Virtual-Dot11Radio Virtual dot11 interface
Virtual-PPP Virtual PPP interface
Virtual-Template Virtual Template interface
Virtual-TokenRing Virtual TokenRing
vmi Virtual Multipoint Interface
SanJose1(config-router)#neighbor 172.16.32.1 update-source loopback0 // USE LOOPBACK 0 AS THE SOURCE IP ADDRESS FOR ALL BGP MESSAGES IF MULTIPLE PATHS EXIST TO THE BGP NEIGHBOR
SanJose2(config)#router bgp 64512
SanJose2(config-router)#neighbor 172.16.64.1 remote-as 64512
SanJose2(config-router)#neighbor 172.16.64.1 update-source loopback0
SanJose2(config-router)#
*Jan 3 09:11:22.983: %BGP-5-ADJCHANGE: neighbor 172.16.64.1 Up
SanJose2#show ip bgp neighbors
BGP neighbor is 172.16.64.1, remote AS 64512, internal link
BGP version 4, remote router ID 172.16.64.1
BGP state = Established, up for 00:00:23
Last read 00:00:23, last write 00:00:23, hold time is 180, keepalive interval is 60 seconds
Neighbor capabilities:
Route refresh: advertised and received(new)
New ASN Capability: advertised and received
Address family IPv4 Unicast: advertised and received
Message statistics:
InQ depth is 0
OutQ depth is 0
Sent Rcvd
Opens: 1 1
Notifications: 0 0
Updates: 0 0
Keepalives: 1 1
Route Refresh: 0 0
Total: 2 2
Default minimum time between advertisement runs is 0 seconds
For address family: IPv4 Unicast
BGP table version 1, neighbor version 0/0
Output queue size : 0
Index 1, Offset 0, Mask 0x2
1 update-group member
Sent Rcvd
Prefix activity: ---- ----
Prefixes Current: 0 0
Prefixes Total: 0 0
Implicit Withdraw: 0 0
Explicit Withdraw: 0 0
Used as bestpath: n/a 0
Used as multipath: n/a 0
Outbound Inbound
Local Policy Denied Prefixes: -------- -------
Total: 0 0
Number of NLRIs in the update sent: max 0, min 0
Address tracking is enabled, the RIB does have a route to 172.16.64.1
Connections established 1; dropped 0
Last reset never
Transport(tcp) path-mtu-discovery is enabled
Connection state is ESTAB, I/O status: 1, unread input bytes: 0
Connection is ECN Disabled, Mininum incoming TTL 0, Outgoing TTL 255
Local host: 172.16.32.1, Local port: 179
Foreign host: 172.16.64.1, Foreign port: 44852
Connection tableid (VRF): 0
Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes)
Event Timers (current time is 0x10DF68):
Timer Starts Wakeups Next
Retrans 3 0 0x0
TimeWait 0 0 0x0
AckHold 2 1 0x0
SendWnd 0 0 0x0
KeepAlive 0 0 0x0
GiveUp 0 0 0x0
PmtuAger 0 0 0x0
DeadWait 0 0 0x0
Linger 0 0 0x0
ProcessQ 0 0 0x0
iss: 3034847281 snduna: 3034847354 sndnxt: 3034847354 sndwnd: 16312
irs: 4118955732 rcvnxt: 4118955805 rcvwnd: 16312 delrcvwnd: 72
SRTT: 99 ms, RTTO: 1539 ms, RTV: 1440 ms, KRTT: 0 ms
minRTT: 8 ms, maxRTT: 300 ms, ACK hold: 200 ms
Status Flags: passive open, gen tcbs
Option Flags: nagle, path mtu capable
IP Precedence value : 6
Datagrams (max data segment is 536 bytes):
Rcvd: 5 (out of order: 0), with data: 2, total data bytes: 72
Sent: 4 (retransmit: 0, fastretransmit: 0, partialack: 0, Second Congestion: 0), with data: 2, total
data bytes: 72
Packets received in fast path: 0, fast processed: 0, slow path: 0
fast lock acquisition failures: 0, slow path: 0
ISP(config)#router bgp 200
ISP(config-router)#neighbor 192.168.1.6 remote-as 64512 // DIFFERENT ASN FOR EBGP PEER
ISP(config-router)#neighbor 192.168.1.2 remote-as 64512 // NO NEED FOR update-source SINCE THERE'S ONLY ONE PATH AVAILABLE
EXIST TO BGP PEER
ISP(config-router)#network 192.168.100.0
SanJose1(config)#ip route 172.16.0.0 255.255.0.0 null0
SanJose1(config)#router bgp 64512
SanJose1(config-router)#neighbor 192.168.1.5 remote-as 200
SanJose1(config-router)#network 172.16.0.0
SanJose1(config-router)#
*Jan 3 08:37:41.055: %BGP-5-ADJCHANGE: neighbor 192.168.1.5 Up
SanJose1#show ip bgp neighbors
BGP neighbor is 172.16.32.1, remote AS 64512, internal link
BGP version 4, remote router ID 172.16.32.1
BGP state = Established, up for 00:03:54
Last read 00:00:57, last write 00:00:17, hold time is 180, keepalive interval is 60 seconds
Neighbor capabilities:
Route refresh: advertised and received(new)
New ASN Capability: advertised and received
Address family IPv4 Unicast: advertised and received
Message statistics:
InQ depth is 0
OutQ depth is 0
Sent Rcvd
Opens: 1 1
Notifications: 0 0
Updates: 1 0
Keepalives: 4 4
Route Refresh: 0 0
Total: 6 5
Default minimum time between advertisement runs is 0 seconds
For address family: IPv4 Unicast
BGP table version 2, neighbor version 2/0
Output queue size : 0
Index 1, Offset 0, Mask 0x2
1 update-group member
Sent Rcvd
Prefix activity: ---- ----
Prefixes Current: 1 0
Prefixes Total: 1 0
Implicit Withdraw: 0 0
Explicit Withdraw: 0 0
Used as bestpath: n/a 0
Used as multipath: n/a 0
Outbound Inbound
Local Policy Denied Prefixes: -------- -------
Total: 0 0
Number of NLRIs in the update sent: max 1, min 1
Address tracking is enabled, the RIB does have a route to 172.16.32.1
Connections established 1; dropped 0
Last reset never
Transport(tcp) path-mtu-discovery is enabled
Connection state is ESTAB, I/O status: 1, unread input bytes: 0
Connection is ECN Disabled, Mininum incoming TTL 0, Outgoing TTL 255
Local host: 172.16.64.1, Local port: 44852
Foreign host: 172.16.32.1, Foreign port: 179
Connection tableid (VRF): 0
Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes)
Event Timers (current time is 0x143C14):
Timer Starts Wakeups Next
Retrans 7 0 0x0
TimeWait 0 0 0x0
AckHold 6 2 0x0
SendWnd 0 0 0x0
KeepAlive 0 0 0x0
GiveUp 0 0 0x0
PmtuAger 1 0 0x19B684
DeadWait 0 0 0x0
Linger 0 0 0x0
ProcessQ 0 0 0x0
iss: 4118955732 snduna: 4118955916 sndnxt: 4118955916 sndwnd: 16201
irs: 3034847281 rcvnxt: 3034847430 rcvwnd: 16236 delrcvwnd: 148
SRTT: 182 ms, RTTO: 1073 ms, RTV: 891 ms, KRTT: 0 ms
minRTT: 8 ms, maxRTT: 300 ms, ACK hold: 200 ms
Status Flags: active open
Option Flags: nagle, path mtu capable
IP Precedence value : 6
Datagrams (max data segment is 536 bytes):
Rcvd: 12 (out of order: 0), with data: 6, total data bytes: 148
Sent: 10 (retransmit: 0, fastretransmit: 0, partialack: 0, Second Congestion: 0), with data: 6, total
data bytes: 183
Packets received in fast path: 0, fast processed: 0, slow path: 0
fast lock acquisition failures: 0, slow path: 0
BGP neighbor is 192.168.1.5, remote AS 200, external link
BGP version 4, remote router ID 192.168.100.1
BGP state = Established, up for 00:00:27
Last read 00:00:27, last write 00:00:27, hold time is 180, keepalive interval is 60 seconds
Neighbor capabilities:
Route refresh: advertised and received(new)
New ASN Capability: advertised and received
Address family IPv4 Unicast: advertised and received
Message statistics:
InQ depth is 0
OutQ depth is 0
Sent Rcvd
Opens: 1 1
Notifications: 0 0
Updates: 1 0
Keepalives: 2 1
Route Refresh: 0 0
Total: 4 2
Default minimum time between advertisement runs is 30 seconds
For address family: IPv4 Unicast
BGP table version 3, neighbor version 3/0
Output queue size : 0
Index 2, Offset 0, Mask 0x4
2 update-group member
Sent Rcvd
Prefix activity: ---- ----
Prefixes Current: 1 1
Prefixes Total: 1 1
Implicit Withdraw: 0 0
Explicit Withdraw: 0 0
Used as bestpath: n/a 0
Used as multipath: n/a 0
Outbound Inbound
Local Policy Denied Prefixes: -------- -------
Bestpath from this peer: 1 n/a
Total: 1 0
Number of NLRIs in the update sent: max 1, min 1
Address tracking is enabled, the RIB does have a route to 192.168.1.5
Connections established 1; dropped 0
Last reset never
Transport(tcp) path-mtu-discovery is enabled
Connection state is ESTAB, I/O status: 1, unread input bytes: 0
Connection is ECN Disabled, Mininum incoming TTL 0, Outgoing TTL 1
Local host: 192.168.1.6, Local port: 48273
Foreign host: 192.168.1.5, Foreign port: 179
Connection tableid (VRF): 0
Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes)
Event Timers (current time is 0x147674):
Timer Starts Wakeups Next
Retrans 3 0 0x0
TimeWait 0 0 0x0
AckHold 3 1 0x0
SendWnd 0 0 0x0
KeepAlive 0 0 0x0
GiveUp 0 0 0x0
PmtuAger 1 0 0x1D0754
DeadWait 0 0 0x0
Linger 0 0 0x0
ProcessQ 0 0 0x0
iss: 1364026979 snduna: 1364027124 sndnxt: 1364027124 sndwnd: 16240
irs: 1747390620 rcvnxt: 1747390766 rcvwnd: 16239 delrcvwnd: 145
SRTT: 99 ms, RTTO: 1539 ms, RTV: 1440 ms, KRTT: 0 ms
minRTT: 8 ms, maxRTT: 300 ms, ACK hold: 200 ms
Status Flags: active open
Option Flags: nagle, path mtu capable
IP Precedence value : 6
Datagrams (max data segment is 1460 bytes):
Rcvd: 6 (out of order: 0), with data: 4, total data bytes: 145
Sent: 7 (retransmit: 0, fastretransmit: 0, partialack: 0, Second Congestion: 0), with data: 4, total
data bytes: 144
Packets received in fast path: 0, fast processed: 0, slow path: 0
fast lock acquisition failures: 0, slow path: 0
SanJose1#show ip bgp summary
BGP router identifier 172.16.64.1, local AS number 64512
BGP table version is 3, main routing table version 3
2 network entries using 264 bytes of memory
2 path entries using 104 bytes of memory
3/2 BGP path/bestpath attribute entries using 504 bytes of memory
1 BGP AS-PATH entries using 24 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
Bitfield cache entries: current 2 (at peak 2) using 64 bytes of memory
BGP using 960 total bytes of memory
BGP activity 2/0 prefixes, 2/0 paths, scan interval 60 secs
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
172.16.32.1 4 64512 7 7 3 0 0 00:05:06 0
192.168.1.5 4 200 4 5 3 0 0 00:01:28 1
SanJose2(config)#ip route 172.16.0.0 255.255.0.0 null0
SanJose2(config)#router bgp 64512
SanJose2(config-router)#neighbor 192.168.1.1 remote-as 200
SanJose2(config-router)#network 172.16.0.0
SanJose2(config-router)#
*Jan 3 09:17:21.507: %BGP-5-ADJCHANGE: neighbor 192.168.1.1 Up
SanJose2#show ip bgp summary
BGP router identifier 172.16.32.1, local AS number 64512
BGP table version is 5, main routing table version 5
2 network entries using 264 bytes of memory
4 path entries using 208 bytes of memory
5/2 BGP path/bestpath attribute entries using 840 bytes of memory
1 BGP AS-PATH entries using 24 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
Bitfield cache entries: current 2 (at peak 2) using 64 bytes of memory
BGP using 1400 total bytes of memory
BGP activity 2/0 prefixes, 4/0 paths, scan interval 60 secs
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
172.16.64.1 4 64512 9 9 5 0 0 00:06:24 2
192.168.1.1 4 200 5 4 4 0 0 00:00:25 1
ISP#clear ip bgp *
ISP#
*Jan 3 09:59:21.235: %BGP-5-ADJCHANGE: neighbor 192.168.1.2 Down User reset
*Jan 3 09:59:21.239: %BGP-5-ADJCHANGE: neighbor 192.168.1.6 Down User reset
*Jan 3 09:59:25.547: %BGP-5-ADJCHANGE: neighbor 192.168.1.6 Up
*Jan 3 09:59:34.763: %BGP-5-ADJCHANGE: neighbor 192.168.1.2 Up
ISP#ping 172.16.64.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.64.1, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
ISP#ping 172.16.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
ISP#ping 172.16.32.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.32.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
ISP#ping 172.16.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
ISP#show ip bgp
BGP table version is 3, local router ID is 192.168.100.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 172.16.0.0 192.168.1.2 0 0 64512 i // SanJose2 WAS CHOSEN AS NEXT HOP DUE TO LOWER ROUTER ID 172.16.32.1 VS SanJose1 ROUTER ID 172.16.64.1 IF ALL PATH ATTRIBUTES ARE EQUAL
* 192.168.1.6 0 0 64512 i
*> 192.168.100.0 0.0.0.0 0 32768 i
ISP#ping 172.16.1.1 source 192.168.100.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
Packet sent with a source address of 192.168.100.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/21/24 ms
ISP#ping 172.16.32.1 source 192.168.100.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.32.1, timeout is 2 seconds:
Packet sent with a source address of 192.168.100.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
ISP#ping 172.16.1.2 source 192.168.100.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:
Packet sent with a source address of 192.168.100.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
ISP#ping 172.16.64.1 source 192.168.100.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.64.1, timeout is 2 seconds:
Packet sent with a source address of 192.168.100.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/21/24 ms
ISP(config)#router bgp 200
ISP(config-router)#network 192.168.1.0 mask 255.255.255.252
ISP(config-router)#network 192.168.1.4 mask 255.255.255.252
ISP(config-router)#do show ip bgp
BGP table version is 5, local router ID is 192.168.100.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 172.16.0.0 192.168.1.2 0 0 64512 i
* 192.168.1.6 0 0 64512 i
*> 192.168.1.0/30 0.0.0.0 0 32768 i
*> 192.168.1.4/30 0.0.0.0 0 32768 i
*> 192.168.100.0 0.0.0.0 0 32768 i
SanJose1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 4 subnets, 2 masks
D 172.16.32.0/24 [90/2297856] via 172.16.1.2, 00:20:13, Serial0/0/1
S 172.16.0.0/16 is directly connected, Null0
C 172.16.1.0/24 is directly connected, Serial0/0/1
C 172.16.64.0/24 is directly connected, Loopback0
192.168.1.0/30 is subnetted, 2 subnets
B 192.168.1.0 [20/0] via 192.168.1.5, 00:00:55
C 192.168.1.4 is directly connected, Serial0/0/0
B 192.168.100.0/24 [20/0] via 192.168.1.5, 00:07:59
SanJose2#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 4 subnets, 2 masks
C 172.16.32.0/24 is directly connected, Loopback0
S 172.16.0.0/16 is directly connected, Null0
C 172.16.1.0/24 is directly connected, Serial0/0/1
D 172.16.64.0/24 [90/2297856] via 172.16.1.1, 00:20:49, Serial0/0/1
192.168.1.0/30 is subnetted, 2 subnets
C 192.168.1.0 is directly connected, Serial0/0/0
B 192.168.1.4 [20/0] via 192.168.1.1, 00:01:00
B 192.168.100.0/24 [20/0] via 192.168.1.1, 00:08:35
SanJose2#show ip bgp
BGP table version is 10, local router ID is 172.16.32.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 172.16.0.0 0.0.0.0 0 32768 i
* i 172.16.64.1 0 100 0 i
r i192.168.1.0/30 192.168.1.5 0 100 0 200 i
r> 192.168.1.1 0 0 200 i
* i192.168.1.4/30 192.168.1.5 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
* i192.168.100.0 192.168.1.5 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
SanJose2(config)#router bgp 64512
SanJose2(config-router)#neighbor 172.16.64.1 ?
activate Enable the Address Family for this Neighbor
advertise-map specify route-map for conditional advertisement
advertisement-interval Minimum interval between sending BGP routing updates
allowas-in Accept as-path with my AS present in it
capability Advertise capability to the peer
default-originate Originate default route to this neighbor
description Neighbor specific description
disable-connected-check one-hop away EBGP peer using loopback address
distribute-list Filter updates to/from this neighbor
dmzlink-bw Propagate the DMZ link bandwidth
ebgp-multihop Allow EBGP neighbors not on directly connected
networks
fall-over session fall on peer route lost
filter-list Establish BGP filters
inherit Inherit a template
local-as Specify a local-as number
maximum-prefix Maximum number of prefixes accepted from this peer
next-hop-self Disable the next hop calculation for this neighbor
next-hop-unchanged Propagate next hop unchanged for iBGP paths to this
neighbor
password Set a password
peer-group Member of the peer-group
prefix-list Filter updates to/from this neighbor
remote-as Specify a BGP neighbor
remove-private-as Remove private AS number from outbound updates
route-map Apply route map to neighbor
route-reflector-client Configure a neighbor as Route Reflector client
send-community Send Community attribute to this neighbor
send-label Send NLRI + MPLS Label to this peer
shutdown Administratively shut down this neighbor
soft-reconfiguration Per neighbor soft reconfiguration
timers BGP per neighbor timers
translate-update Translate Update to MBGP format
transport Transport options
ttl-security BGP ttl security check
unsuppress-map Route-map to selectively unsuppress suppressed
routes
update-source Source of routing updates
version Set the BGP version to match a neighbor
weight Set default weight for routes from this neighbor
SanJose2(config-router)#neighbor 172.16.64.1 next-hop-self // SET THE IP ADDRESS OF THE BORDER ROUTER IN DIFFERENT ASN; NOT MODIFIED FOR IBGP PEER
SanJose1(config)#router bgp 64512
SanJose1(config-router)#neighbor 172.16.32.1 next-hop-self
SanJose1#clear ip bgp 172.16.32.1
SanJose1#
*Jan 3 08:54:54.947: %BGP-5-ADJCHANGE: neighbor 172.16.32.1 Down User reset
*Jan 3 08:54:55.311: %BGP-5-ADJCHANGE: neighbor 172.16.32.1 Up
SanJose2#show ip bgp
BGP table version is 10, local router ID is 172.16.32.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.64.1 0 100 0 i
*> 0.0.0.0 0 32768 i
r i192.168.1.0/30 172.16.64.1 0 100 0 200 i
r> 192.168.1.1 0 0 200 i
* i192.168.1.4/30 172.16.64.1 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
* i192.168.100.0 172.16.64.1 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
SanJose1#show ip bgp
BGP table version is 8, local router ID is 172.16.64.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.32.1 0 100 0 i
*> 0.0.0.0 0 32768 i
* i192.168.1.0/30 172.16.32.1 0 100 0 200 i
*> 192.168.1.5 0 0 200 i
r i192.168.1.4/30 172.16.32.1 0 100 0 200 i
r> 192.168.1.5 0 0 200 i
* i192.168.100.0 172.16.32.1 0 100 0 200 i
*> 192.168.1.5 0 0 200 i
SanJose2#show ip bgp
BGP table version is 10, local router ID is 172.16.32.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.64.1 0 100 0 i
*> 0.0.0.0 0 32768 i
r i192.168.1.0/30 172.16.64.1 0 100 0 200 i
r> 192.168.1.1 0 0 200 i
* i192.168.1.4/30 172.16.64.1 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
* i192.168.100.0 172.16.64.1 0 100 0 200 i
*> 192.168.1.1 0 0 200 i
SanJose1(config)#route-map PRIMARY_T1_IN permit 10
SanJose1(config-route-map)#set ?
as-path Prepend string for a BGP AS-path attribute
automatic-tag Automatically compute TAG value
clns OSI summary address
comm-list set BGP community list (for deletion)
community BGP community attribute
dampening Set BGP route flap dampening parameters
default Set default information
extcomm-list Set BGP/VPN extended community list (for deletion)
extcommunity BGP extended community attribute
global Set to global routing table
interface Output interface
ip IP specific information
ipv6 IPv6 specific information
level Where to import route
local-preference BGP local preference path attribute
metric Metric value for destination routing protocol
metric-type Type of metric for destination routing protocol
mpls-label Set MPLS label for prefix
nlri BGP NLRI type
origin BGP origin code
tag Tag value for destination routing protocol
traffic-index BGP traffic classification number for accounting
vrf Define VRF name
weight BGP weight for routing table
SanJose1(config-route-map)#set local-preference ?
<0-4294967295> Preference value
<cr>
SanJose1(config-route-map)#set local-preference 150 // ADVERTISED BETWEEN IBGP PEER FOR OUTBOUND TRAFFIC; DEFAULT VALUE IS 100
SanJose1(config-route-map)#exit
SanJose1(config)#router bgp 64512
SanJose1(config-router)#neighbor 192.168.1.5 route-map PRIMARY_T1_IN in
SanJose2(config)#route-map SECONDARY_T1_IN permit 10
SanJose2(config-route-map)#set local-preference 125
SanJose2(config-route-map)#exit
SanJose2(config)#router bgp 64512
SanJose2(config-router)#neighbor 192.168.1.1 route-map SECONDARY_T1_IN in
SanJose1#clear ip bgp * soft
SanJose2#clear ip bgp * soft
SanJose1#show ip bgp
BGP table version is 11, local router ID is 172.16.64.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.32.1 0 100 0 i
*> 0.0.0.0 0 32768 i
*> 192.168.1.0/30 192.168.1.5 0 150 0 200 i
r> 192.168.1.4/30 192.168.1.5 0 150 0 200 i
*> 192.168.100.0 192.168.1.5 0 150 0 200 i
SanJose2#show ip bgp
BGP table version is 16, local router ID is 172.16.32.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.64.1 0 100 0 i
*> 0.0.0.0 0 32768 i
r>i192.168.1.0/30 172.16.64.1 0 150 0 200 i
r 192.168.1.1 0 125 0 200 i
*>i192.168.1.4/30 172.16.64.1 0 150 0 200 i
* 192.168.1.1 0 125 0 200 i
*>i192.168.100.0 172.16.64.1 0 150 0 200 i
* 192.168.1.1 0 125 0 200 i
ISP#show ip bgp
BGP table version is 5, local router ID is 192.168.100.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 172.16.0.0 192.168.1.2 0 0 64512 i
* 192.168.1.6 0 0 64512 i
*> 192.168.1.0/30 0.0.0.0 0 32768 i
*> 192.168.1.4/30 0.0.0.0 0 32768 i
*> 192.168.100.0 0.0.0.0 0 32768 i
SanJose2#ping
Protocol [ip]:
Target IP address: 192.168.100.1
Repeat count [5]:
Datagram size [100]:
Timeout in seconds [2]:
Extended commands [n]: y
Source address or interface: 172.16.32.1
Type of service [0]:
Set DF bit in IP header? [no]:
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]: record // RECORDS PACKET'S HOP/IP ADDRESS
Number of hops [ 9 ]:
Loose, Strict, Record, Timestamp, Verbose[RV]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.100.1, timeout is 2 seconds:
Packet sent with a source address of 172.16.32.1
Packet has IP options: Total option bytes= 39, padded length=40
Record route: <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
Reply to request 0 (20 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2) SanJose2 S0/0/1
(192.168.1.6) SanJose1 S0/0/0
(192.168.100.1) ISP LOOPBACK0
(192.168.1.1) ISP S0/0/0
(172.16.32.1) <*> SanJose2 LOOPBACK2 // RETURN TRAFFIC PREFERS SanJose2
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 1 (20 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 2 (24 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 3 (20 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 4 (20 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/20/24 ms
SanJose1(config)#route-map PRIMARY_T1_MED_OUT permit 10
SanJose1(config-route-map)#set ?
as-path Prepend string for a BGP AS-path attribute
automatic-tag Automatically compute TAG value
clns OSI summary address
comm-list set BGP community list (for deletion)
community BGP community attribute
dampening Set BGP route flap dampening parameters
default Set default information
extcomm-list Set BGP/VPN extended community list (for deletion)
extcommunity BGP extended community attribute
global Set to global routing table
interface Output interface
ip IP specific information
ipv6 IPv6 specific information
level Where to import route
local-preference BGP local preference path attribute
metric Metric value for destination routing protocol
metric-type Type of metric for destination routing protocol
mpls-label Set MPLS label for prefix
nlri BGP NLRI type
origin BGP origin code
tag Tag value for destination routing protocol
traffic-index BGP traffic classification number for accounting
vrf Define VRF name
weight BGP weight for routing table
SanJose1(config-route-map)#set metric ?
+/-<metric> Add or subtract metric
<0-4294967295> Metric value or Bandwidth in Kbits per second
SanJose1(config-route-map)#set metric 50 // BGP MED (LOWER IS BETTER); ADVERTISED TO EBGP PEER FOR INBOUND TRAFFIC
SanJose1(config-route-map)#exit
SanJose1(config)#router bgp 64512
SanJose1(config-router)#neighbor 192.168.1.5 route-map PRIMARY_T1_MED_OUT ?
in Apply map to incoming routes
out Apply map to outbound routes
SanJose1(config-router)#neighbor 192.168.1.5 route-map PRIMARY_T1_MED_OUT out // POLICY TO FORCE ISP ROUTER TO RETURN TRAFFIC VIA SanJose1
SanJose2(config)#route-map SECONDARY_T1_MED_OUT permit 10
SanJose2(config-route-map)#set metric 75
SanJose2(config-route-map)#exit
SanJose2(config)#router bgp 64512
SanJose2(config-router)#neighbor 192.168.1.1 route-map SECONDARY_T1_MED_OUT out
SanJose1#clear ip bgp * soft
SanJose2#clear ip bgp * soft
ISP#show ip bgp
BGP table version is 6, local router ID is 192.168.100.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* 172.16.0.0 192.168.1.2 75 0 64512 i // SanJose2 HOP
*> 192.168.1.6 50 0 64512 i // SanJose1 HOP
*> 192.168.1.0/30 0.0.0.0 0 32768 i
*> 192.168.1.4/30 0.0.0.0 0 32768 i
*> 192.168.100.0 0.0.0.0 0 32768 i
SanJose1#show ip bgp // MED REFLECTED ON ISP/UPSTREAM ROUTER
BGP table version is 11, local router ID is 172.16.64.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* i172.16.0.0 172.16.32.1 0 100 0 i
*> 0.0.0.0 0 32768 i
*> 192.168.1.0/30 192.168.1.5 0 150 0 200 i
r> 192.168.1.4/30 192.168.1.5 0 150 0 200 i
*> 192.168.100.0 192.168.1.5 0 150 0 200 i
SanJose2#ping
Protocol [ip]:
Target IP address: 192.168.100.1
Repeat count [5]:
Datagram size [100]:
Timeout in seconds [2]:
Extended commands [n]: y
Source address or interface: 172.16.32.1
Type of service [0]:
Set DF bit in IP header? [no]:
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]: record
Number of hops [ 9 ]:
Loose, Strict, Record, Timestamp, Verbose[RV]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.100.1, timeout is 2 seconds:
Packet sent with a source address of 172.16.32.1
Packet has IP options: Total option bytes= 39, padded length=40
Record route: <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
Reply to request 0 (48 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1) ISP LOOPBACK0 IP ADDRESS
(192.168.1.5) ISP S0/0/0
(172.16.1.1) SanJose1 S0/0/1 // ISP NOW PREFERS SanJose1 FOR RETURN TRAFFIC
(172.16.32.1) <*> SanJose2 LOOPBACK0 IP ADDRESS
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 1 (28 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.5)
(172.16.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 2 (32 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.5)
(172.16.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 3 (28 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.5)
(172.16.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Reply to request 4 (32 ms). Received packet has options
Total option bytes= 40, padded length=40
Record route:
(172.16.1.2)
(192.168.1.6)
(192.168.100.1)
(192.168.1.5)
(172.16.1.1)
(172.16.32.1) <*>
(0.0.0.0)
(0.0.0.0)
(0.0.0.0)
End of list
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/33/48 ms
SanJose1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 4 subnets, 2 masks
D 172.16.32.0/24 [90/2297856] via 172.16.1.2, 00:58:53, Serial0/0/1
S 172.16.0.0/16 is directly connected, Null0
C 172.16.1.0/24 is directly connected, Serial0/0/1
C 172.16.64.0/24 is directly connected, Loopback0
192.168.1.0/30 is subnetted, 2 subnets
B 192.168.1.0 [20/0] via 192.168.1.5, 00:39:35
C 192.168.1.4 is directly connected, Serial0/0/0
B 192.168.100.0/24 [20/0] via 192.168.1.5, 00:46:39
SanJose1(config)#ip default-network 192.168.100.0
SanJose1(config)#end
SanJose1#show ip route
*Jan 3 09:29:16.403: %SYS-5-CONFIG_I: Configured from console by console
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is 192.168.1.5 to network 192.168.100.0
172.16.0.0/16 is variably subnetted, 4 subnets, 2 masks
D 172.16.32.0/24 [90/2297856] via 172.16.1.2, 00:59:23, Serial0/0/1
S 172.16.0.0/16 is directly connected, Null0
C 172.16.1.0/24 is directly connected, Serial0/0/1
C 172.16.64.0/24 is directly connected, Loopback0
192.168.1.0/30 is subnetted, 2 subnets
B 192.168.1.0 [20/0] via 192.168.1.5, 00:40:04
C 192.168.1.4 is directly connected, Serial0/0/0
B* 192.168.100.0/24 [20/0] via 192.168.1.5, 00:47:09
ISP#tclsh
ISP(tcl)#foreach address {
+>192.168.100.1
+>172.16.64.1
+>172.16.32.1
+>192.168.1.1
+>192.168.1.2
+>192.168.1.5
+>192.168.1.6
+>172.16.1.1
+>172.16.1.2
+>} {
+>ping $address }
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.100.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/4 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.64.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/13/16 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.32.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.5, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/28 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.6, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
