[c-nsp] Packet Loss During the Backbone Network Converge

[Xu Hu]

Anybody have any idea?

Thanks and regards,
Xu Hu

On 26 Jul, 2012, at 21:43, Xu Hu <jstuxuhu0816 at gmail.com> wrote:

> Hi All,
> 
> Below is the network topology, i ping from CE-2 to CE-1, during i shutdown the PE-4, have some packet drops.
> CE connect to the backbone network using HSRP, the hear beat is through the CE switch. PE-1 and PE-3 is the active gateway, PE-2 and PE-4 is the standby one.
> 
> PE equipment running OSPF as IGP, then on the top having MP-iBGP, MPLS VPN, MPLS TE auto-tunnel.
> 
> Normally i send traffic from CE-2 to CE-1 will use the path "CE-2>PE-3>PE-1>CE-1".  The active tunnel from PE-3 to PE-1 is directly path, the backup tunnel is path through PE-4 to PE-2 to PE-1.
> So when i shutdown the router of PE-4, the active tunnel should be no impact, but there is some packet drops. Don't understand why.
> 
> Firstly, i think it because of the HSRP, then i ping from PE-3 to CE-1 (Under vrf) when i shutdown PE-4, but the result is also have packet drops.
> So i think is because of backbone network converge. But i am not sure which part will need to converge.
> 
>    <--CE-1-->
>      |          | 
>      |          |
>      |          |
>     PE-1----PE-2
>      |          | 
>      |          |
>      |          |
>     PE-3----PE-4
>      |          | 
>      |          |
>      |          |
>     <--CE-2-->
> 
> Will appreciate for any comments.
> 
> Best Regards,
> Hu Xu
> 
> 
>