[j-nsp] 10GE xe-0/0/0 traffic anomaly

[Richard A Steenbergen]

On Mon, May 19, 2008 at 01:40:57PM +0200, Witold Koscielniak wrote:
> M120 has only one interface - xe-0/0/0 with many 802.1q subinterfaces.
> So traffic on xe-0/0/0 should be exactly symmetrical (in/out = 1) but it is not!!
> 
> Mrtg shows that traffic on 10G summit is exactly symmetrical but on xe-0/0/0
> is asymmetrical:
> 
> admin at Juniper_M120> monitor interface traffic
> Interface    Link     Input bytes        (bps)      Output bytes        (bps)
>   xe-0/0/0      Up  61944473131097 (318338324)    30951930138936 (156175948)
> 
> Input traffic is approximatly twice geater than output (in/out = 2).
> 
> What is happen? Why input traffic is greater than output traffic.
> What doubled input traffic on xe-0/0/0?

I've seen something similar with AE member interfaces (PR274396) on I-chip 
based platforms (M120 and MX) where it double-counts stats if you have 
family mpls enabled. I haven't seen that exact behavior on regular 
interfaces, but I've seen several other counter bugs in the last few 
months (mostly on AE's) so it might be related.

-- 
Richard A Steenbergen <ras at e-gerbil.net>       http://www.e-gerbil.net/ras
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)