Hi Dennis, I've your going to issue a REFER directly after 200 OK, why not simply 302 redirect instead?
Kind Regards, Jaco On 2019/08/29 13:18, Joshua C. Colp wrote: > On Thu, Aug 29, 2019, at 7:45 AM, Dennis Buteyn wrote: >> Been trying to perform a blind transfer for hours with a SIP client I'm >> developing (using Sofia). Every time I sent a REFER request, Asterisk >> would respond with 202, followed by a NOTIFY containing the ominous >> phrase "503 Service Unavailable (can't handle one-legged xfers)". >> >> At first, I thought maybe my SDP isn't good enough. So I copied some >> Zoiper SDP. Nope, still receive 503. >> >> So I turned Asterisk debug and verbose up to 11 and went caving in >> Asterisk sources. As far as I could tell, it was >> ast_bridge_transfer_blind that failed. >> >> Then it hit me... maybe the transfer failed because the bridge hasn't >> been created yet? Maybe I'm sending my REFER too soon? >> >> So I added a sleep(1) just before sending my REFER... success?!? >> >> Now, obviously sleep(1) isn't a good solution and I don't recall a >> minimum required delay in the specs. Should I wait for the first RTP >> packet to arrive? Is this a bug? I'm confused. > There is no minimum specified in the spec because it's dependent on the > remote side itself (in this case Asterisk). Asterisk only allows blind > transferring a channel (can't blind transfer the dialplan for example). Since > things happen asynchronously if you do it too fast at answer there is > certainly a window whereby it could not yet be in a situation where a > transfer is possible and thus the transfer would fail. Waiting for RTP to > arrive could work. > -- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- asterisk-dev mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-dev
