Cisco NX-OS Troubleshooting Guide, Release 4.0 - Troubleshooting Routing [Cisco NX-OS Software]

Table Of Contents

Troubleshooting Routing

Routing Overview

Initial Troubleshooting Checklist

Troubleshooting Routing

Troubleshooting Routing

This chapter describes troubleshooting procedures for virtual device contexts (Routing).

This chapter includes the following topics:

•Routing Overview

•Initial Troubleshooting Checklist

•Troubleshooting Routing

Routing Overview

Layer 3 routing involves two basic activities: 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 introduces the virtual device context (VDC), which provides 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).

See the Cisco NX-OS Unicast Routing Configuration Guide and the Cisco NX-OS Multicast Routing Configuration Guide for more information on routing.

Initial Troubleshooting Checklist

Begin troubleshooting routing issues by checking the following issues first:

Checklist

Checkoff

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

Troubleshooting Routing

To troubleshoot basic routing issues, follow these steps:

Step 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.

Step 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
Step 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
Step 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
Step 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
Step 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: 1.0.0.1, IP subnet: 1.0.0.0/24
  ...
  IP multicast groups locally joined:
      224.0.0.2  224.0.0.1  224.0.0.13
  ...
Step 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
Step 8 Verify that the routing protocol is registered with the routing information base (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:
...
Step 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