Solved: SPAN 3560 destination port disconnect

sefimizra · ‎09-24-2015

Hello,

I configured SPAN (monitor session) on my 3560 switch and it works fine until the destination port disconnect from any reason (shut no shut, cable unplug, restart destination computer). than the destination port don't show any traffic from the source ports.

the problem fix just after I reconfigured the monitor session again.

the configuration I made:

SW_Server_1#monitor session 1 source interface Gi0/1 - 2 , Gi0/4
SW_Server_1#monitor session 1 destination interface Gi0/3

SW_Server_1#sh monitor session all
Session 1
---------
Type : Local Session
Source Ports :
Both : Gi0/1-2,Gi0/4
Destination Ports : Gi0/3
Encapsulation : Native
Ingress : Disabled

Any Ideas??

Thanks,

Sefi

Peter Paluch · ‎09-24-2015

Mark,

This sounds more like a bug to me. An asymmetry in the amount of captured traffic and the capacity of the egress interface should not pose any problem. Quoting from documentation to Catalyst 3560:

SPAN sessions do not interfere with the normal operation of the switch. However, an oversubscribed SPAN destination, for example, a 10-Mb/s port monitoring a 100-Mb/s port, can result in dropped or lost packets.

Surely, disconnecting and reconnecting a destination port shouldn't cause the entire SPAN session to stop working entirely.

Best regards,
Peter

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