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Can't answer phone

This morning a remote site called and said they couldn't answer the ringing phones. We have a centralized call-manager with a 2801 voice-gateway using h323. Phones are plugged into a 3750 POE Switch w/ auto-qos configured. PC's are daisy-chained off phones. Voice /Data vlans are configured and ports that have routers plugged in are mls qos trust dscp and ports that have phones plugged in are mls qos trust cos. Users could dial out fine, but anytime a call came it, it would ring and when they picked up the phone they couldn't hear anything. Finally after rebooting the switch, everything turned back to normal. Any ideas where to look to figure out what caused the issue? Thanks.

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Green

Re: Can't answer phone

Hi,

"Users could dial out fine, but anytime a call came it, it would ring and when they picked up the phone they couldn't hear anything"

The incoming PSTN calls arrived at the central location and are routed to remote site?

The topology is sth like that?

IP Phone 3750 ---> Router --- WAN --- Router 2801 --- CCM ?

Did Outgoing calls work fine using the same H323 GW?

"Users could dial out fine, but anytime a call came it, it would ring and when they picked up the phone they couldn't hear anything."

The IP Phone to IP Phone (same loc) calls worked fine?

The IP Phone to Remote IP Phone calls worked fine?

Which IOS version in the 3750?

First time issue? Or has been reocurring during the time?

One way audio or no-way audio?

Looks like the switch wasnt forwarding packets to its default GW (could be a loop, misconfigured STP,HW issue, buffers filling, not sure).

We would need IOS version, sniffer trace at phone level and at switch level and CCM detail trace to see H245 OLCack from GW.

HTH

//G

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