SV-56:~# ip route default via 172.16.56.200 dev eth1 172.16.56.0/24 dev eth1 proto kernel scope link src 172.16.56.1 172.20.20.0/24 dev eth0 proto kernel scope link src 172.20.20.3
RP/0/RP0/CPU0:RT-03#ping 172.16.56.1 Mon Dec 23 04:08:33.908 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.56.1 timeout is 2 seconds: ..^C Success rate is 0 percent (0/2)
RP/0/RP0/CPU0:RT-03#sh ip route 172.16.56.1 Mon Dec 23 04:03:16.188 UTC Routing entry for 172.16.56.0/24 Known via “connected”, distance 0, metric 0 (connected) Installed Dec 23 02:09:12.234 for 01:54:03 Routing Descriptor Blocks directly connected, via GigabitEthernet0/0/0/2 Route metric is 0 No advertising protos. RP/0/RP0/CPU0:RT-03#sh ip int GigabitEthernet 0/0/0/2 Mon Dec 23 04:19:31.060 UTC GigabitEthernet0/0/0/2 is Up, ipv4 protocol is Up Vrf is default (vrfid 0x60000000) Internet address is 172.16.56.202/24
RP/0/RP0/CPU0:RT-03#ping 172.16.55.1 Mon Dec 23 04:22:42.030 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.55.1 timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms
RP/0/RP0/CPU0:RT-03#sh hsrp Mon Dec 23 03:34:58.207 UTC IPv4 Groups: P indicates configured to preempt. | Interface Grp Pri P State Active addr Standby addr Group addr Gi0/0/0/2 55 110 P Active local unknown 172.16.56.200 IPv6 Groups: P indicates configured to preempt. | Interface Grp Pri P State Active addr Standby addr Group addr
RP/0/RP0/CPU0:RT-03#ping 172.16.56.201 Mon Dec 23 04:11:02.352 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.56.201 timeout is 2 seconds: …^C Success rate is 0 percent (0/3)
RP/0/RP0/CPU0:RT-02#ping 172.16.56.1 Mon Dec 23 03:47:43.134 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.56.1 timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/2 ms
RP/0/RP0/CPU0:RT-02#ping 172.16.55.1 Mon Dec 23 03:51:40.431 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.55.1 timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/2 ms
RP/0/RP0/CPU0:RT-02#sh hsrp Mon Dec 23 03:43:37.715 UTC IPv4 Groups: P indicates configured to preempt. | Interface Grp Pri P State Active addr Standby addr Group addr Gi0/0/0/2 55 100 Active local unknown 172.16.56.200 IPv6 Groups: P indicates configured to preempt. | Interface Grp Pri P State Active addr Standby addr Group addr
RP/0/RP0/CPU0:RT-01#sh ip route 172.16.56.1 Mon Dec 23 02:17:58.012 UTC Routing entry for 172.16.56.0/24 Known via “bgp 55”, distance 200, metric 0, type internal Installed Dec 23 02:10:26.906 for 00:07:31 Routing Descriptor Blocks 3.3.3.3, from 3.3.3.3 Route metric is 0 No advertising protos.
RP/0/RP0/CPU0:RT-01#sh ip bgp Tue Dec 24 09:43:24.957 UTC BGP router identifier 1.1.1.1, local AS number 55 Status codes: s suppressed, d damped, h history, * valid, > best i – internal, r RIB-failure, S stale, N Nexthop-discard Origin codes: i – IGP, e – EGP, ? – incomplete Network Next Hop Metric LocPrf Weight Path *> 172.16.55.0/24 0.0.0.0 0 32768 i * i172.16.56.0/24 2.2.2.2 0 100 0 i *>i 3.3.3.3 0 100 0 i
RP/0/RP0/CPU0:RT-01#sh ip bgp 172.16.56.0 255.255.255.0 detail Mon Dec 23 02:19:45.085 UTC BGP routing table entry for 172.16.56.0/24 Versions: Process bRIB/RIB SendTblVer Speaker 7 7 Flags: 0x00001001+0x20010000+0x00000000 Last Modified: Dec 23 02:10:26.806 for 00:09:18 Paths: (2 available, best #2) Not advertised to any peer Path #1: Received by speaker 0 Flags: 0x2000000000020005+0x00, import: 0x020 Not advertised to any peer Local 2.2.2.2 (metric 16) from 2.2.2.2 (2.2.2.2), if-handle 0x00000000 Origin IGP, metric 0, localpref 100, valid, internal Received Path ID 0, Local Path ID 0, version 0 Path #2: Received by speaker 0 Flags: 0x2000000001060005+0x00, import: 0x020 Not advertised to any peer Local 3.3.3.3 (metric 11) from 3.3.3.3 (3.3.3.3), if-handle 0x00000000 Origin IGP, metric 0, localpref 100, valid, internal, best, group-best Received Path ID 0, Local Path ID 1, version 7
RP/0/RP0/CPU0:RT-03#conf t RP/0/RP0/CPU0:RT-03(config)#interface GigabitEthernet 0/0/0/2 RP/0/RP0/CPU0:RT-03(config-if)#shutdown RP/0/RP0/CPU0:RT-03(config-if)#commit
RP/0/RP0/CPU0:RT-01#sh ip bgp Tue Dec 24 09:48:56.072 UTC BGP router identifier 1.1.1.1, local AS number 55 BGP generic scan interval 60 secs Non-stop routing is enabled BGP table state: Active Table ID: 0xe0000000 RD version: 10 BGP table nexthop route policy: BGP main routing table version 10 BGP NSR Initial initsync version 6 (Reached) BGP NSR/ISSU Sync-Group versions 0/0 BGP scan interval 60 secs Status codes: s suppressed, d damped, h history, * valid, > best i – internal, r RIB-failure, S stale, N Nexthop-discard Origin codes: i – IGP, e – EGP, ? – incomplete Network Next Hop Metric LocPrf Weight Path *> 172.16.55.0/24 0.0.0.0 0 32768 i *>i172.16.56.0/24 2.2.2.2 0 100 0 i Processed 2 prefixes, 2 paths
RP/0/RP0/CPU0:RT-01#ping 172.16.56.1 Tue Dec 24 09:49:18.997 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.56.1 timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/3 ms
RP/0/RP0/CPU0:RT-01#ping 172.16.0.2 Mon Dec 23 07:35:12.596 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.0.2 timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/2 ms RP/0/RP0/CPU0:RT-01#
SV-01から81.10.0.1にPingが到達すること。
SV-01:~# ping -c3 81.10.0.1 PING 81.10.0.1 (81.10.0.1) 56(84) bytes of data. 64 bytes from 81.10.0.1: icmp_seq=1 ttl=61 time=1.87 ms 64 bytes from 81.10.0.1: icmp_seq=2 ttl=61 time=1.82 ms 64 bytes from 81.10.0.1: icmp_seq=3 ttl=61 time=1.68 ms — 81.10.0.1 ping statistics — 3 packets transmitted, 3 received, 0% packet loss, time 2003ms rtt min/avg/max/mdev = 1.678/1.787/1.868/0.080 ms SV-01:~#
RP/0/RP0/CPU0:RT-01#ping 172.16.0.2 Mon Dec 30 06:02:09.935 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.0.2 timeout is 2 seconds: ….. Success rate is 0 percent (0/5)
SV-02(81.10.0.1)宛はOK
RP/0/RP0/CPU0:RT-01#ping 81.10.0.1 Mon Dec 30 07:21:38.937 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 81.10.0.1 timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms RP/0/RP0/CPU0:RT-01#
パケットの転送先はBGP Next Hop（2.2.2.2）を参照し、ルーティングテーブルの再起検索でOSPFでRT-02向けのGi0/0/0/0から送出されることがわかる。
RP/0/RP0/CPU0:RT-01#sh ip route Mon Dec 23 07:24:14.302 UTC Codes: C – connected, S – static, R – RIP, B – BGP, (>) – Diversion path D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area Gateway of last resort is 172.20.20.1 to network 0.0.0.0 S* 0.0.0.0/0 [1/0] via 172.20.20.1, 01:09:06, MgmtEth0/RP0/CPU0/0 L 1.1.1.1/32 is directly connected, 01:09:14, Loopback0 O 2.2.2.2/32 [110/2] via 192.168.0.2, 01:08:57, GigabitEthernet0/0/0/0 B 10.1.81.0/30 [200/0] via 2.2.2.2, 01:07:55 B 10.2.92.0/30 [200/0] via 2.2.2.2, 01:07:55 B 10.83.0.0/16 [200/0] via 2.2.2.2, 00:09:55 B 13.12.0.0/20 [200/0] via 2.2.2.2, 00:09:55 B 14.13.0.0/16 [200/0] via 2.2.2.2, 00:09:55 B 15.16.0.0/20 [200/0] via 2.2.2.2, 00:09:55 B 172.16.0.0/20 [200/0] via 2.2.2.2, 00:09:55 B 172.16.0.0/21 [200/0] via 2.2.2.2, 00:09:55 C 172.20.20.0/24 is directly connected, 01:09:06, MgmtEth0/RP0/CPU0/0 L 172.20.20.7/32 is directly connected, 01:09:06, MgmtEth0/RP0/CPU0/0 C 192.168.0.0/30 is directly connected, 01:09:08, GigabitEthernet0/0/0/0 L 192.168.0.1/32 is directly connected, 01:09:08, GigabitEthernet0/0/0/0
RT-02に入って改めてPingすると結果は相変わらずNG。
RP/0/RP0/CPU0:RT-02#ping 172.16.0.2 Mon Dec 30 06:26:41.225 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.0.2 timeout is 2 seconds: ….. Success rate is 0 percent (0/5)
RT-02でshow ip routeをたたくと、今度は①と②でnext-hopが異なることが分かる。※RT-02からiBGPで広報されたときはLo0(2.2.2.2)だった。
RP/0/RP0/CPU0:RT-02#sh ip route Mon Dec 30 06:26:57.628 UTC Codes: C – connected, S – static, R – RIP, B – BGP, (>) – Diversion path 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, E – EGP i – ISIS, L1 – IS-IS level-1, L2 – IS-IS level-2 ia – IS-IS inter area, su – IS-IS summary null, * – candidate default U – per-user static route, o – ODR, L – local, G – DAGR, l – LISP A – access/subscriber, a – Application route M – mobile route, r – RPL, t – Traffic Engineering, (!) – FRR Backup path Gateway of last resort is 172.20.20.1 to network 0.0.0.0 S* 0.0.0.0/0 [1/0] via 172.20.20.1, 02:45:39, MgmtEth0/RP0/CPU0/0 O 1.1.1.1/32 [110/2] via 192.168.0.1, 02:45:31, GigabitEthernet0/0/0/0 L 2.2.2.2/32 is directly connected, 02:45:47, Loopback0 C 10.1.81.0/30 is directly connected, 02:45:41, GigabitEthernet0/0/0/1 L 10.1.81.1/32 is directly connected, 02:45:41, GigabitEthernet0/0/0/1 C 10.2.92.0/30 is directly connected, 02:45:41, GigabitEthernet0/0/0/2 L 10.2.92.1/32 is directly connected, 02:45:41, GigabitEthernet0/0/0/2 B 10.83.0.0/16 [20/0] via 10.1.81.2, 02:44:26 B 13.12.0.0/20 [20/0] via 10.1.81.2, 02:44:26 B 14.13.0.0/16 [20/0] via 10.1.81.2, 02:44:26 B 15.16.0.0/20 [20/0] via 10.1.81.2, 02:44:26 B 81.10.0.0/16 [20/0] via 10.1.81.2, 02:44:26 B 172.16.0.0/20 [20/0] via 10.2.92.2, 02:44:26 B 172.16.0.0/21 [20/0] via 10.1.81.2, 02:44:26 C 172.20.20.0/24 is directly connected, 02:45:39, MgmtEth0/RP0/CPU0/0 L 172.20.20.6/32 is directly connected, 02:45:39, MgmtEth0/RP0/CPU0/0 C 192.168.0.0/30 is directly connected, 02:45:41, GigabitEthernet0/0/0/0 L 192.168.0.2/32 is directly connected, 02:45:41, GigabitEthernet0/0/0/0 RP/0/RP0/CPU0:RT-02#
RP/0/RP0/CPU0:RT-02#sh int description | include “Gi0/0/0/1|Gi0/0/0/2” Mon Dec 30 06:41:32.170 UTC Gi0/0/0/1 up up to-RT-81-external Gi0/0/0/2 up up to-RT-92-external
RT-02で採択経路の再確認
RP/0/RP0/CPU0:RT-02#sh ip route 172.16.0.2 Mon Dec 30 06:29:47.085 UTC Routing entry for 172.16.0.0/21 Known via “bgp 55”, distance 20, metric 0 Tag 81, type external Installed Dec 30 03:42:30.931 for 02:47:16 Routing Descriptor Blocks 10.1.81.2, from 10.1.81.2, BGP external Route metric is 0 No advertising protos. RP/0/RP0/CPU0:RT-02#
RP/0/RP0/CPU0:RT-02#sh ip cef 172.16.0.2 Mon Dec 30 06:43:38.030 UTC 172.16.0.0/21, version 23, internal 0x5000001 0x40 (ptr 0x874038e8) [1], 0x0 (0x0), 0x0 (0x0) Updated Dec 30 03:42:30.934 local adjacency to GigabitEthernet0/0/0/1 Prefix Len 21, traffic index 0, precedence n/a, priority 4 gateway array (0x8828d798) reference count 6, flags 0x2010, source rib (7), 0 backups [1 type 3 flags 0x48501 (0x88331cf8) ext 0x0 (0x0)] LW-LDI[type=0, refc=0, ptr=0x0, sh-ldi=0x0] gateway array update type-time 1 Dec 30 03:42:30.934 LDI Update time Dec 30 03:42:30.934 via 10.1.81.2/32, 2 dependencies, recursive, bgp-ext [flags 0x6020] path-idx 0 NHID 0x0 [0x8740aa20 0x0] next hop 10.1.81.2/32 via 10.1.81.2/32 Load distribution: 0 (refcount 1) Hash OK Interface Address 0 Y GigabitEthernet0/0/0/1 10.1.81.2
RP/0/RP0/CPU0:RT-92#ping 172.16.0.2 Mon Dec 30 07:05:10.519 UTC Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.0.2 timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/51/188 ms RP/0/RP0/CPU0:RT-92#sh ip route 172.16.0.2 Mon Dec 30 07:05:19.844 UTC
RP/0/RP0/CPU0:RT-02#sh ip bgp neighbor 10.2.92.2 received routes Mon Dec 30 07:51:16.321 UTC BGP router identifier 2.2.2.2, local AS number 55 BGP generic scan interval 60 secs Non-stop routing is enabled BGP table state: Active Table ID: 0xe0000000 RD version: 16 BGP table nexthop route policy: BGP main routing table version 16 BGP NSR Initial initsync version 13 (Reached) BGP NSR/ISSU Sync-Group versions 0/0 BGP scan interval 60 secs Status codes: s suppressed, d damped, h history, * valid, > best i – internal, r RIB-failure, S stale, N Nexthop-discard Origin codes: i – IGP, e – EGP, ? – incomplete Network Next Hop Metric LocPrf Weight Path *> 172.16.0.0/20 10.2.92.2 0 92 i Processed 1 prefixes, 1 paths
RP/0/RP0/CPU0:RT-92#sh ip route | include 172 Mon Dec 30 07:53:12.667 UTC S* 0.0.0.0/0 [1/0] via 172.20.20.1, 04:11:56, MgmtEth0/RP0/CPU0/0 B 172.16.0.0/20 [200/0] via 0.0.0.0, 04:10:52, Null0 B 172.16.0.0/21 [20/0] via 10.2.92.1, 04:10:45 C 172.16.0.0/24 is directly connected, 04:11:58, GigabitEthernet0/0/0/1 L 172.16.0.1/32 is directly connected, 04:11:58, GigabitEthernet0/0/0/1 S 172.16.8.0/22 [1/0] via 172.16.0.2, 04:11:58, GigabitEthernet0/0/0/1 S 172.16.12.0/22 [1/0] via 172.16.0.2, 04:11:58, GigabitEthernet0/0/0/1 C 172.20.20.0/24 is directly connected, 04:11:56, MgmtEth0/RP0/CPU0/0 L 172.20.20.8/32 is directly connected, 04:11:56, MgmtEth0/RP0/CPU0/0
RP/0/RP0/CPU0:RT-92#sh ip bgp neighbor 10.2.92.1 advertised-routes Mon Dec 30 07:57:28.915 UTC Network Next Hop From AS Path 172.16.0.0/20 10.2.92.2 Local Aggregate 92i Processed 1 prefixes, 1 paths
RP/0/RP0/CPU0:RT-02#sh ip bgp neighbor 10.1.81.2 advertised-routes Mon Dec 30 08:39:29.355 UTC Network Next Hop From AS Path 172.16.0.0/20 10.1.81.1 10.2.92.2 55 92i 192.168.0.0/24 10.1.81.1 Local 55i Processed 2 prefixes, 2 paths RP/0/RP0/CPU0:RT-02#
