[asterisk-users] Asterisk SIP handling - why 491 Request Pending response

Tomasz Zieleniewski tzieleniewski at gmail.com
Sat Dec 22 08:51:11 CST 2007


Hi,

The message that asterisk receives is not a retransmission but this is the
same message but it enters asterisk from other sip proxy  which is not a
loop.
The flow is the following

Asterisk      SIP Proxy (Location Service)
INVITE (to registrar)
--------------------->
INVITE (to voicemail when not registered)
<--------------------

when message enters asterisk for the second time it ofcorse has some extra
SIP
specific header like Record-Route and Via and the Request-URI is changed.
And this causes 491 response.
Can I do something about this?
Can this behaviour be controlled, what do I have to change in the message so
that asterisk won't treat it with 491 response?

Thanks
Tomasz

On Dec 21, 2007 7:28 PM, Terry Wilson <twilson at digium.com> wrote:

> What is the reason for such response?
>
>
> SIP/2.0 491 Request Pending
> Via: SIP/2.0/UDP 192.168.129.74:5160;branch=z9hG4bK17c3.17db29e7.0
> ;received=192.168.129.74
> Via: SIP/2.0/UDP 192.168.129.74 ;branch=z9hG4bK17c3.23083974.0
> Via: SIP/2.0/UDP 192.168.129.74:5070;branch=z9hG4bK5b33ae78;rport=5070
> From: "IPFon" <sip:0225761853 at 192.168.129.74:5070>;tag=as7217acbc
> To: <sip:tzl at voip.touk.pl>;tag=as7217acbc
> Call-ID: 307fda656066a7e264e85cea0742e601 at 192.168.129.74
> CSeq: 102 INVITE
> User-Agent: Asterisk PBX
> Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY
> Supported: replaces
> Content-Length: 0
> X-Asterisk-HangupCause: Normal Clearing
> X-Asterisk-HangupCauseCode: 16
>
>
> Asterisk will send a 491 Request Pending when it is currently processing
> an INIVTE on a particular call and it gets another INVITE that isn't a
> retransmission.
>
>
> _______________________________________________
> --Bandwidth and Colocation Provided by http://www.api-digital.com--
>
> asterisk-users mailing list
> To UNSUBSCRIBE or update options visit:
>   http://lists.digium.com/mailman/listinfo/asterisk-users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.digium.com/pipermail/asterisk-users/attachments/20071222/5ee9fa1a/attachment.htm 


More information about the asterisk-users mailing list