Locked up SIP extension on your Asterisk server? Me too. Here’s how I released it.

I have struggled with this issue for a while on a large deployment (6 servers hosting ~175 extensions). An extension would complete a call, and the SIP channel on the extension side would fail to release when the call terminated, resulting in the extension appearing to be busy to the server. All calls go straight to voicemail. Calls can be initiated just fine, but I could not find a resolution for releasing the channel short of restarting the server, which is obviously not the desired method of resolution. This issues is addressed in the Asterisk ticket here: https://issues.asterisk.org/jira/browse/ASTERISK-19455, but no short-term resolution to the immediate problem of the channel that won’t die.

SO… Today when this issue happened, I stuck with it longer that I had in the past, experimenting with trying to stop the channel. Here’s how I was able to release the extension without a complete reboot of the server. Continue reading

Windows Server 2008 Time Syncronization

In struggling with time synchronization under Windows 2008 R2, I came across an issue that had me stumped for a bit.  I have a client with Windows 2008 R2 Standard running in a virtual machine in Hyper-v.  I have configured it to sync time from pool.ntp.org using the w32tm as instructed here, here and here.

The Hyper-v host is getting it’s time reference from the PDC that it is hosting as well.  When the client complained that the time was off by something like 8 minutes, I began checking into the issue.  When running

w32tm /stripchart /computer: target /samples: n /dataonly

I was getting back sporadic 0x800705b4 errors mixed in with the reports that my server was 378.023845629 (or so) seconds off.  I didn’t see reference to that anywhere I Googled.  for it to error every time?  Sure.  Mixed in the same results with successful connections?  Not one.  I checked the firewall settings anyway.  Also, forcing sync had no effect. The clock was still off by three hundred and seventy whatever seconds.

Finally I found my problem.  In integration services, time sync to the host is one of the options.  So I was syncing my host to my PCD which was trying to sync pool.ntp.org, but being overridden by the integration services and syncing to the host.

Moral?  Virtual machine settings –> Management –> Integration Services –> Time Synchronization?  Uncheck it.