Enhanced show interfaces command

 

It's amazing how many options (most of them still undocumented) the show interfaces command accepts in IOS release 12.4T (I won't even start guessing when each one was introduced, if you're running old IOS releases, please feel free to comment):

• show interfaces description displays interface names, L1 and L2 status (line and line-protocol status) and interface description. Extremely handy if you want to check which interfaces are up/down.
• show interfaces counters protocol status displays the L3 protocols active on each interface.
• show interfaces summary displays the state of various interface queues and related drop counters in a nice tabular format.
• show interfaces accounting displays per-protocol in/out counters.

Here are a few sample printouts:

a1#show interfaces description
Interface      Status         Protocol Description
Fa0/0          up             up       Central LAN
Fa0/1          admin down     down
Se0/0/0        up             up       Frame Relay
Se0/0/0.100    up             up       Link to B1
Se0/1/0        admin down     down
Se0/1/1        admin down     down
Lo0            up             up
 
a1#show interfaces counters protocol status
Protocols allocated:
 FastEthernet0/0: Other, IP, DEC MOP, ARP, CDP
 FastEthernet0/1: Other, IP
 Serial0/0/0: Other, IP, CDP
 Serial0/1/0: Other, IP
 Serial0/1/1: Other, IP
 Loopback0: Other, IP
 VoIP-Null0: Other, IP
 
a1#show interfaces summary
 
 *: interface is up
 IHQ: pkts in input hold queue     IQD: pkts dropped from input queue
 OHQ: pkts in output hold queue    OQD: pkts dropped from output queue
 RXBS: rx rate (bits/sec)          RXPS: rx rate (pkts/sec)
 TXBS: tx rate (bits/sec)          TXPS: tx rate (pkts/sec)
 TRTL: throttle count
 
  Interface        IHQ   IQD  OHQ   OQD  RXBS RXPS  TXBS TXPS TRTL
------------------------------------------------------------------
* FastEthernet0/0    0     0    0     0     0    0     0    0    0
  FastEthernet0/1    0     0    0     0     0    0     0    0    0
* Serial0/0/0        0     0    0     0     0    0     0    0    0
* Serial0/0/0.100    -     -    -     -     -    -     -    -   -
  Serial0/1/0        0     0    0     0     0    0     0    0    0
  Serial0/1/1        0     0    0     0     0    0     0    0    0
* Loopback0          0     0    0     0     0    0     0    0    0
NOTE:No separate counters are maintained for subinterfaces
     Hence Details of subinterface are not shown
 
a1#show interfaces accounting
FastEthernet0/0 Central LAN
      Protocol    Pkts In   Chars In   Pkts Out  Chars Out
         Other          0          0        490      29400
            IP       2737     216847       3052     424422
       DEC MOP          0          0          8        616
           ARP          5        316         12        720
           CDP         82      30914         84      29563
Interface FastEthernet0/1 is disabled
 
Serial0/0/0 Frame Relay
      Protocol    Pkts In   Chars In   Pkts Out  Chars Out
         Other          0          0        490       6370
            IP        515      43748       1034      87608
           CDP         83      26477        168      55272

Posted to Cisco IOS Hints and Tricks by Ivan Pepelnjak
© Copyright Ivan Pepelnjak