No subject

600
I'm subscribed to a "buddy" on my Polycom phone. Periodically I'd get this
error: 'Incoming call: Got SIP response 500 "Internal Server Error" back
from 10.1.1.200'.

Additional Description

We have six(6) Polycom 601 attenendant consoles monitoring roughly
forty(40) Polycom 430 phones each for a total of one hundred (100) or so
watchers/hints.

To reproduce the behaviour you need only interrupt chan_sip via reload, or
an Asterisk restart.  Once this has been done, presence notifications sent
to the phones will no longer take place properly.  It is unclear as to
whether this problem is due to the Asterisk system not sending the right
messages, or the Polycom not responding properly to a properly formatted
message.  But, after a while, the phones will start sending messages back
in response to messages from Asterisk that say "Internal Server Error". 
One thing is for certain.  After the channel is interrupted, by reload or
restart, presence no longer works.
======================================================================
Relationships       ID      Summary
----------------------------------------------------------------------
related to          0005164 "Presence" subscription cause...
has duplicate       0011118 Polycom Phones & Hints
====================================================================== 

---------------------------------------------------------------------- 
 dtyoo - 11-06-07 17:53  
---------------------------------------------------------------------- 
We also run into this problem quite a bit.  We have a large environment
running asterisk 1.4.13 and remote polycom endpoints running sip 2.1.1 and
sip 2.1.2.  Any time we restart asterisk all the subscriptions on the
server are lost.  Some phones seem to recover from this during
re-subscription.  Some phones do not.  I'm still trying to figure out why
some phones do not recover.  It seems to be more of a problem on phones
which have many subscriptions.

Oej-

In case you want to see a sip capture of the "Internal Server Error" it is
attached in a scenario where the phone did recover on re-subscription.  The
error is given by the polycom when it gets the notify immediately following
the re-subscribe.  I think its getting freaked out by a CSeq id it is not
expecting.  Perhaps it would be best if asterisk forced the polycom to
subcribe from scratch when it gets a re-subscribe and there is are no
existing subscription?  The RFC seems to say that this could be
accomplished by setting the Subscription-State to "terminated".  Of course
we would have to see if the polycoms do the right thing with this header. 

Issue History 
Date Modified   Username       Field                    Change               
====================================================================== 
11-06-07 17:53  dtyoo          Note Added: 0073263                          
======================================================================