I've got a customer that has SIP trunks on a IPO 9.0 Partner edition. They are saying that they can make outgoing calls but can't receive incoming calls. When you call their main number you hear the message that “you have reached a nonworking number. Announcement 14 switch 18-3.”. Their SIP provider is Allied and they are saying that there’s a routing issue with the PBX. They’re getting 503 service unavailable errors to their SBC. There have been no configuration changes so says the customer. I will be comparing the original cfg file saved to my laptop to their current cfg to make sure. The customer also said that now it seems they are able to receive calls for about 30 minutes and then it goes back down. This pattern repeats itself throughout the day. My questions are has anyone experienced this issue before and where do I begin to troubleshoot? I checked alarms and there are none. Strange. Thanks for any help you can give.

Larry

Authorized Avaya Business Partner