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New Member

Loopback 0 - input/output statistics

Good day.

Under which conditions do you get :

--input bytes = 0

--output bytes = 800.000.000 (or some other LARGE number)

on the loopback interface?

In our case it is being used for telnet and OSPF.

When I try pinging to the interface there is no increase - it stays on zero.

Other interfaces on the router (1720) are the serial and the fastEthernet.




Re: Loopback 0 - input/output statistics

When you ping to the loopback interface, are you sourcing the ping from the router or outside the router? I believe that if you ping that interface from within the router, the counters will not increase. Are you having a problem telneting to the router or with OSPF? Or are you just curious about the counters?

New Member

Re: Loopback 0 - input/output statistics

I have no problems with the router as such, whether telnetting or with OSPF - I am merely curious as to why the output counters are so high and the input so low (well, actually, "Zero")

Sourcing from outside as well as from the ethernet interface.

You see we are always on the lookout for strange things due to the amount of bugs/viruses running around.

So maybe this is what the router does when it is bored? Since it can't twiddle its thumbs.....? :))


Re: Loopback 0 - input/output statistics


Are you using lo 0 for your source for TACACS or SNMP ? If you are this could be the source of the output bytes