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New Member

SIP/2.0 503 Service Unavailable

hello,

I have a sip trunk from ccm 5.x to an operator gateway and can make calls to pstn without problems.

The problem is that when i receive a call from the sip gateway via the sip trunk, the call manager sends SIP/2.0 503 Service Unavailable.

NOTE: i receive the full number from the trunk and convert it to the extension via translation-pattern.

Is there any special configuration to solve this issue in inbound calls?

Thank you,

Met.

7 REPLIES
Silver

Re: SIP/2.0 503 Service Unavailable

Try to enable inbound/outbound H323 Faststart on the CallManager.

New Member

Re: SIP/2.0 503 Service Unavailable

but in the sip trunk config that options does not exist...right?

Thanks!

New Member

Re: SIP/2.0 503 Service Unavailable

what about trying setting "MTP required" to yes?

is it enabled in the first place?

New Member

Re: SIP/2.0 503 Service Unavailable

yes it is.

tnx.

New Member

Re: SIP/2.0 503 Service Unavailable

can't anyone point a direction?

SIP/2.0 503 Service Unavailable

Warning: 399 "Routing Failed:..."

Only in Incoming calls from SIP Gateway to CUCM. Outgoing calls are OK.

Thanks,

Met.

New Member

Re: SIP/2.0 503 Service Unavailable

can't anyone point a direction?

SIP/2.0 503 Service Unavailable

Warning: 399 "Routing Failed:..."

Only in Incoming calls from SIP Gateway to CUCM. Outgoing calls are OK.

Thanks,

Met.

New Member

Re: SIP/2.0 503 Service Unavailable

Ok. Problem solved.

Provider provided sip gateway local address and didnt have nat to their public address.

After establishing SIP trunk between CUCM cluster and public sip address, calls work incoming and outgoing.

Thanks for suggestions,

Regards,

Met.

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