[asterisk-dev] Asterisk + DAHDI failure-resistance (non)

Oron Peled oron.peled at xorcom.com
Sat Jul 6 07:07:41 CDT 2013


_Today's Asterisk+DAHDI state:_
     *  If a single channel/span breaks...
     *  On the next asterisk restart -- no DAHDI channels at all!
     *  Is it acceptable in 2013?

This could have been fixed for years.

_What happened on the DAHDI side?_
     *  In 2008[1] this problem was presented, with proposed solution.
     *  Few months later we had a prototype[2] of the DAHDI side.
     *  Tried to revive interest in 2010[3].
     *  In 2011 Shaun Raffle started a big revamp of DAHDI in different direction. 
This resulted in the pinned-spans[4] scheme which was part of DAHDI-*2.6.0*.
     *  Since Nov-2011, it also included the required fixes for DAHDI-tools (see the 
dahdi_cfg '-S<span>' and '-C<chan_list>' options).
     *  Which means DAHDI is "ready" -- each channel/span may be handled 
independently of the others.
_What happened in Asterisk?_
     *  Dynamic channel removal (DAHDI_EVENT_REMOVED)was added some 
eons ago (in the Zaptel days).
     *  It had a bug with D-Channels. Tzafrir uploaded a fix to review-board (726)
[5] some 3 years ago -- it still lingers there instead of being applied to all 
supported asterisk versions.
     *  Dynamic channel addition code was uploaded to review-board (1598)[6] in 
Nov-2011 and keeps waiting there...
     *  With these patches, Asterisk+DAHDI is fully dynamic, where we can 
add/remove channels and spans at run-time without affecting the PBX.
     *  But non of this is committed to trunk :-(

So with all the multi-year effort to solve this problem, we are still in square-one.

Releasing Asterisk 12 in this state is a major failure in my book.
Are your customers happy when a single channel failure make the whole PBX 
drop dead? If not, why don't you review those patches?

Sorry for the not-so-happy tone, but...

Oron Peled                                 Voice: +972-4-8228492
oron at actcom.co.il                  http://users.actcom.co.il/~oron
          "A standard for copy protection is as premature
           as a standard for teleportation."
                   --- Noted computer security expert and
                       Princeton University Professor
                       Edward Felten.

[1] http://lists.digium.com/pipermail/asterisk-dev/2008-July/033805.html
[2] http://svnview.digium.com/svn/dahdi?view=revision&revision=5443
[3] https://gitorious.org/asterisk-tools/dahdi-linux/commit/6e5f2bb05fd309bacab570c80e6304b487d9c19b
[4] http://lists.digium.com/pipermail/asterisk-dev/2011-October/051954.html
[5] https://reviewboard.asterisk.org/r/726/
[6] https://reviewboard.asterisk.org/r/1598/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.digium.com/pipermail/asterisk-dev/attachments/20130706/a8f5ee24/attachment.htm>

More information about the asterisk-dev mailing list