SPAN and ERSPAN Destination

[mfurnival]

Hi,

Is it possible to have an interface that is both a destination in a local SPAN session and a destination in an ERSPAN session?

So for example I have Switch A and B. On Switch A G0/1 is destination in a local monitor session and is also a destination in an ERSPAN session from switch B.

[Mark Malone]

Hi

I have not fully tested this but I just ran the syntax and it does not give any errors when you set the erspan and local span to the same dest port , usually if its an issue it will block it

#sh run | i dest
monitor session 1 destination interface Gi2/5
monitor session 3 type erspan-destination
 destination interface Gi2/5

[Austin Sabio]

Multiple SPAN sessions are not allowed. 

"Only one destination port is allowed per SPAN session, and the same port cannot be a destination port for multiple SPAN sessions. Therefore, you cannot have two SPAN sessions that use the same destination port."

"A destination port can participate in only one SPAN session at a time. A destination port in one SPAN session cannot be a destination port for a second SPAN session."

http://www.cisco.com/c/en/us/support/docs/switches/catalyst-6500-series-switches/10570-41.html

[mfurnival]

Yeah I read that statement too and was not sure how to interpret it. I am asking if a port can be a destination port in a SPAN session and an ERSPAN session, not two SPAN sessions. 

Unfortunately I don't have any kit at my disposal to test this out on.

[Austin Sabio]

If you're referring to G0/1 as a destination port -typically where the network analyzer is connected- then you cannot use it as a destination port for both sessions, ERSPAN is actually a regular SPAN over GRE-Tunnel. Due to limitation on switch resources as mentioned above.

I hope this helps.