[asterisk-users] SendText causes Retransmission errors

[Kevin P. Fleming]

On 03/20/2012 01:08 PM, Matt Hamilton wrote:
>  > Date: Mon, 19 Mar 2012 10:31:52 -0500
>  > From: kpfleming at digium.com
>
>  > > 502 10.0.1.103 10.0.1.57 Request: CANCEL sip:104 at 10.0.1.57:5060
>  >
>  > Why did Asterisk CANCEL the call here?
>
>
> I assume it's part of the SLA implementation. As I mentioned in my
> original email, I'm using SendText to send a text message when the user
> picks up a line in a SLA setup. In this case, ext 124 is calling 104,
> and one of the lines on 104 is picking it up. Asterisk is connecting to
> that line and cancelling the first request?? (just guessing)
>
> same => n,SendText(hi)
> same => n,SLAStation(4*104_line104)
>
>
>  >
>  > > *503 (for 493) 10.0.1.57 10.0.1.103 Status: 200 OK*
>  > > 524 (503) 10.0.1.57 10.0.1.103 Request: ACK
>  > > sip:8*104_line104 at 10.0.1.103:5060
>  >
>  > This appears to be broken. The listing here claims this ACK is in
>  > response to the '200 OK' in packet 503, which itself was a final
>  > response to the MESSAGE request in packet 493. However, MESSAGE requests
>  > do not use ACK for a three-way handshake like INVITE requests do. In
>  > addition, this packet is going the wrong direction to be an ACK for
>  > packet 503, since it's going the same direction as packet 503 did.
>
>
>
> I use Wireshark to capture the packets, and Wireshark is reporting it
> that way; i.e. saying that Request Frame for the ACK is the OK (for
> MESSAGE). I guess it's incorrect. The order and direction of messages I
> posted in my previous email are taken directly from Wireshark.
>
> Frame 15 is MESSAGE
> Frame 19 is OK (for MESSAGE)
> Frame 20 is ACK (Wireshark is saying the Request Frame is 20 ??)
>
> I tried to post the full SIP capture here, but it got rejected because
> of the size of the post (about 280k).

Yep, that's a lot. The next step is probably to open an issue in our 
issue tracker and upload the capture file there (feel free to compress 
it first to save time and space).

-- 
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
Jabber: kfleming at digium.com | SIP: kpfleming at digium.com | Skype: kpfleming
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
Check us out at www.digium.com & www.asterisk.org