Unanswered Question
Aug 25th, 2007
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When creating a SPAN session in IOS, there is an option on the monitor destination command to preserve any VLAN encapsulation. Is there an equivalent option or method with CatOS?

The CatOS platform is a 6509 w/Sup720-3b running Hybrid CatOS 8.4(4)/IOS 12.2(17d)SXB10.

Migrating to Native IOS is not a viable option at this time.


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a-vazquez Thu, 08/30/2007 - 13:47
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The encapsulation replicate command is supported on 3560/3750 switches but for SPAN only. According to the 3750 config guide:

For RSPAN, the original VLAN ID is lost because it is overwritten by

the RSPAN VLAN identification. Therefore, all packets appear on the

destination port as untagged. "

I think if you have sup720/sup32 under IOS, you can use ERSPAN, which does preserve the original VLAN ID on the ERSPAN destination port.


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