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Giant frames on 6509 interface

Hello community,


our monitoring tools (LMS 4.1) are reporting high error rates on the interfaces interconnecting our backbone (6509-E running s72033-advipservicesk9_wan-mz.122-18.SXF17a.bin, located on 3 sites). Traffic passing through these interfaces is encrypted (SPA-IPSEC-2G). I believe that the high error rate was first reported when encryption was enabled (unfortunately I was on maternity leave back then, so I am not really sure about this).

What I see on the interfaces is a constant increment on giants, as well as an increase on rxOversizedPkt, when issuing the "show counters int" command. The error rate seems to increase with traffic increase.

I do not see any drops or any other CRCs. I am not sure if these giants have any impact on applications or user traffic... The interface mtu is 1600.

Should I be concerned??? I read that this might be a cosmetic bug (


Any thoughts or troubleshooting tips would be highly appreciated.


Thank you in advance,


  • LAN Switching and Routing
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