SPAN session question on two 6509s

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Mar 13th, 2009
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I have two 6509 switch connected via a fiber trunk on the SUP blade.

All vlans are trunked on this trunk.

Both switches have monitor sessions set up on them and I am getting an error trying to create an additional one.

I am thinking I can remove one of them cecause it looks redundant to me:

Switch 1

monitor session 1 source vlan 1 , 5 , 10 - 249

monitor session 1 destination remote vlan 998

monitor session 3 source vlan 250

monitor session 3 destination remote vlan 251

Switch 2

monitor session 1 source vlan 1 , 10 - 249 rx

monitor session 1 destination interface Gi8/40

monitor session 2 source interface Gi8/19

monitor session 2 destination interface Fa4/40

monitor session 6 destination interface Gi8/21

monitor session 6 source remote vlan 251

If switch 2 is monitoring all vlans and is detined for port g8/40, this should collect all information on both switches if all vlans are trunked, correct?

This means I could remove monitor session 1 on switch one (detined for vlan 998) because this would be collected on the other monitor session, correct?

Also, I do not see any ports in vlan 998, how would I collect anything from that monitor session?

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wilson_1234_2 Fri, 03/13/2009 - 06:57
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But is my thinking correct also in that since I am spanning the vlans on switch 2 and all vlans are trunked, the remote span on switch 1 to vlan 998 is redundant?

Is that correct?

Also, on my destination port, does this have to be in any particulr vlan?

For example if it is a workstation that will be collecting, the destination port needs to be in the workstation vlan?

Giuseppe Larosa Fri, 03/13/2009 - 10:29
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Hello Richard,

the destination port doesn't need to be in the remote span vlan.

the remote span vlan is a logical pipe to carry captured traffic using the remote span vlan vlan-id on trunk ports from source switch to destination switch.

on destination switch the remote span vlan is declared the source of the monitor session and so it can be associated to a port that doesn't need to be in the rspan vlan.

Hope to help



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