Cisco Nexus 7000 Series NX-OS Troubleshooting Guide -- Troubleshooting Routing
This article describes troubleshooting procedures for routing.
Information about Troubleshooting Routing Issues
Layer 3 routing involves determining optimal routing paths and packet switching. You can use routing algorithms to calculate the optimal path from the router to a destination. This calculation depends on the algorithm selected, route metrics, and other considerations such as load balancing and alternate path discovery.
Cisco NX-OS uses the virtual device contexts (VDCs) to provide separate management domains per VDC and software fault isolation. Each VDC supports multiple Virtual Routing and Forwarding Instances (VRFs) and multiple routing information bases (RIBs) to support multiple address domains. Each VRF is associated with a routing information base (RIB) and this information is collected by the Forwarding Information Base (FIB).
Initial Troubleshooting Checklist
Begin troubleshooting routing issues by checking the following issues first:
Verify that the routing protocol is enabled.
Verify that the address family is configured if necessary.
Verify that you have configured the correct VRF for your routing protocol.
Use the following commands to display routing information:
- show ip arp
- show ip traffic
- show tcp statistics udp4
- show ip client
- show tcp client
- show ip fib
- show ip process
- show ip route
- show pktmgr interface
- show frame traffic
- show platform fib
- show platform forwarding
- show platform ip
- show vrf
- show vrf interface
To troubleshoot basic routing issues, follow these steps:
1. Verify that the routing protocol is enabled.
switch(config)# show ospf ^ % invalid command detected at '^' marker.
- If the feature is not enabled, Cisco NX-OS reports that the command is invalid. Use the feature command to enable the routing protocol.
2. Verify the configuration for this routing protocol.
switch# show running-config eigrp all version 4.0(1) feature eigrp router eigrp 99 log-neighbor-warnings log-neighbor-changes log-adjacency-changes graceful-restart nsf timers nsf signal 20 distance 90 170 metric weights 0 1 0 1 0 0 metric maximum-hops 100 default-metric 100000 100 255 1 1500 maximum-paths 16 address-family ipv4 unicast log-neighbor-warnings log-neighbor-changes log-adjacency-changes graceful-restart router-id 192.0.2.1 nsf timers nsf signal 20 distance 90 170 metric weights 0 1 0 1 0 0 metric maximum-hops 100 default-metric 100000 100 255 1 1500 maximum-paths 16
3. Verify the VRF configuration for this routing protocol.
switch# show running-config eigrp version 4.0(1) feature eigrp router eigrp 99 address-family ipv4 unicast router-id 192.0.2.1 vrf red stub
4. Check the memory utilization for this routing protocol.
switch# show processes memory | include isis 8913 9293824 bffff1d0/bffff0d0 isis 32243 8609792 bfffe0c0/bfffdfc0 isis
5. Verify that the routing protocol is receiving packets.
switch# show ip client pim Client: pim, uuid: 284, pid: 3839, extended pid: 3839 Protocol: 103, client-index: 10, routing VRF id: 255 Data MTS-SAP: 1519 Data messages, send successful: 2135, failed: 0
6. Verify that the routing protocol is enabled on an interface.
switch# show ip interface loopback0 loopback0, Interface status: protocol-up/link-up/admin-up, iod: 36, Context:"default" IP address: 22.214.171.124, IP subnet: 126.96.36.199/24 ... IP multicast groups locally joined: 188.8.131.52 184.108.40.206 220.127.116.11 ...
7. Verify that the interface is in the correct VRF.
switch(config)# show vrf interface loopback 99 Interface VRF-Name VRF-ID loopback99 default 1
8. Verify that the routing protocol is registered with the RIB.
switch(config)# show routing unicast clients CLIENT: am index mask: 0x00000002 epid: 3908 MTS SAP: 252 MRU cache hits/misses: 2/1 Routing Instances: VRF: management table: base Messages received: Register : 1 Add-route : 2 Delete-route : 1 Messages sent: Add-route-ack : 2 Delete-route-ack : 1 CLIENT: rpm index mask: 0x00000004 epid: 4132 MTS SAP: 348 MRU cache hits/misses: 0/0 Messages received: Register : 1 Messages sent: ... CLIENT: eigrp-99 index mask: 0x00002000 epid: 3148 MTS SAP: 63775 MRU cache hits/misses: 0/1 Routing Instances: VRF: default table: base notifiers: self Messages received: Register : 1 Delete-all-routes : 1 Messages sent: ...
9. Verify that the RIB is interacting with the forwarding plane.
switch# show forwarding distribution multicast client Number of Clients Registered: 3 Client-name Client-id Shared Memory Name igmp 1 N/A mrib 2 /procket/shm/mrib-mfdm m6rib 3 /procket/shm/m6rib-mfdm
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