SIP trunk silliness after peering change

Adam Greene maillist at
Thu Nov 5 04:03:21 UTC 2009


Does this make any sense? We (ASN 11579) peer to (2) WBS routers (ASN 

We lost our link to the primary WBS router. After that, calls coming in 
over our SIP trunks were fine in one direction only. 
Callers could hear us, but we couldn't hear them. After 45 minutes, 
things righted themselves.

Later on the primary WBS link came back up and went down again 5 minutes 
later (not WBS's fault, we brought up and took down the BGP session).

Again we experienced the one-direction-only problem with, 
but this time it lasted 2.50 hours. Again things eventually righted 
themselves without our intervention.

Traces from us to were fine during the outage. We were 
unable to get a trace from to us during the outage. Maybe 
the only way to figure out what is going on is to get that return path 
trace during an outage.

Has anyone else experienced issues of this nature (extended outage of 
voice in one direction only) specifically with SIP trunks 
as a result of simply changing one's peering with one's upstream provider?


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