duplicate packet

Wed Sep 10 12:06:02 UTC 2008

> -----Original Message-----
> From: chloe K [mailto:chloekcy2000 at yahoo.ca]
> Sent: Wednesday, September 10, 2008 6:46 AM
> To: nanog at nanog.org
> Subject: duplicate packet
>
> Hi all
>
> When I ping the ip, I get the duplicate
>
> I check the ip is just one. Why it happens?
>
> Thank you
>
> 64 bytes from 192.168.0.95: icmp_seq=1 ttl=63 time=0.344 ms
> 64 bytes from 192.168.0.95: icmp_seq=1 ttl=63 time=0.401 ms (DUP!)
> 64 bytes from 192.168.0.95: icmp_seq=2 ttl=63 time=0.296 ms
> 64 bytes from 192.168.0.95: icmp_seq=2 ttl=63 time=0.328 ms (DUP!)
> 64 bytes from 192.168.0.95: icmp_seq=3 ttl=63 time=0.291 ms
> 64 bytes from 192.168.0.95: icmp_seq=3 ttl=63 time=0.316 ms (DUP!)
> 64 bytes from 192.168.0.95: icmp_seq=4 ttl=63 time=0.279 ms
> 64 bytes from 192.168.0.95: icmp_seq=4 ttl=63 time=0.309 ms (DUP!)
> 64 bytes from 192.168.0.95: icmp_seq=5 ttl=63 time=0.271 ms
> 64 bytes from 192.168.0.95: icmp_seq=5 ttl=63 time=0.299 ms (DUP!)

Check to see whether or not the port connected to that host is mirrored or in a SPAN VLAN.  Misconfiguration on an analyzer server can cause duplicate traffic to be generated.

-evt