atcomsystems.ca/forum Forums VOIP Phones & IP PBX Cisco Telephones and Systems cisco call manager dropping calls

question from a carrier level. I have an customer using a cisco call manager. The ckt will intermitently drop calls. The pysical layer (LAYER 1) of the pri is clean. but we both see (telco and call manger side ) massive protocol errors(layer 2). then it clears on its own ans is fine for a week or so and teh trouble returns. both parties are set for 5ess custom. Any Idea what whould cause these protcol errors?

Do you have one set to master and the other slave for clocking?

will need to verify clocking on monday, though I did not see any timing errors while in moniter on the span

actually I did not see any errors

I had a customer with similar problems on a traditional PBX. Carrier blamed equipment and vice versa...We went back and forth for months until they switched to a different carrier and ALL problems cleared. Might be time to request a pair change on the PRI.

possible....I need to find out what happened on sat. The last time I have seen this type of issue it was a few bad channels causing sabme msgs to be sent out but for some reasson it would cause the PRI to bounce..real weired what we did was busy out all 23 b-channels and force calls over easch indvisual channel until it failed. kept those channels busied out and the trouble cleared, csr repalced the gateway and problem was resolved. So basically that was going to happen this past saturday, along with additionl testing. If all else fails we are going to have a protocol analyzer brougt to the site and run it behind the smart jack this way we can either eliminite or prove a cpe issue.

It only takes the 24th channel to hose up the whole BTW.

looks liek it was either a protocol handler on the carrier side or a defective router. Teh carrier swung this to a new handler and teh router was repalced....all seems to be working