[j-nsp] Packet Loss in VRF

[Dermot Williams]

Hello List,

 

I've an odd problem with packet loss in a VRF. Our setup is similar to
this diagram:

 

+------+           +-----+           +------+

| PE-A |-----------|  P  |-----------| PE-B |

+------+           +-----+           +------+

 

PE-B has two CE routers attached - as a result it has two interfaces in
the VRF. Let's call these interfaces 'PE-B-1' and 'PE-B-2'. If I conduct
a rapid ping to PE-B-1 with a packet size of 1000, I get a reply rate of
100%. If I conduct another ping with identical parameters to PE-B-2
between 10 and 20 packets in every 1000 are dropped. The ping command
that I'm using is similar to this:

 

ping routing-instance my-vrf size 1000 rapid count 1000 x.x.x.x

 

The config on both interfaces at PE-B is identical, other than the VLAN
ID and IP address. Both interfaces are actually logical interfaces on
the same physical FE. The VRF config is pretty standard and both
interfaces have a CE router attached and full BGP adjacencies
established. In other words, there is absolutely no difference between
the two interfaces.

 

At PE-A, the only difference between the route to PE-B-1 and PE-B-2 is
the VPN label. Since there is only one P device between PE-A and PE-B,
there is no wildly divergent paths through the network that packets to
one address could take over the other.

 

Is there anything else that I need to look at to troubleshoot this? Is
this normal behaviour?

 

Dermot Williams

Senior Network Engineer

Irish Broadband Internet Services Ltd.

 







This message is for the named person's use only. It may contain confidential, proprietary or legally privileged information. No confidentiality or privilege is waived or lost by any mistransmission. If you receive this message in error, please immediately delete it and all copies of it from your system, destroy any hard copies of it and notify the sender. You must not, directly or indirectly, use, disclose, distribute, print, or copy any part of this message if you are not the intended recipient. Irish Broadband and any of its subsidiaries each reserve the right to monitor all e-mail communications through its networks. Any views expressed in this message are those of the individual sender, except where the message states otherwise and the sender is authorized to state them to be the views of any such entity.

Irish Broadband Internet Services Ltd, Registered in Ireland, Number: 357181, Registered Office: Burton Court, Burton Hall Road, Sandyford Industrial Estate, Dublin 18