[asterisk-users] 1000 analogue lines with asterisk

[Tzafrir Cohen]

On Fri, Feb 19, 2016 at 10:52:34AM +1300, Daniel Harper wrote:
> What about leaving the old PBX in place and trunking it via ISDN to the
> asterisk server.
> 
> We use rhino 24 channel bank but are 2U for rhino + 1U for patch panel.
> (RJ21 cable so might be able to use existing ones if they are RJ21)
> 
> Used USB xorcoms a while back, things may of changed but if one is down and
> reboot server then asterisk doesn't come up.

Not with recent versions of DAHDI. Assuming you set auto_assign_spans=0,
DAHDI channel and span numbers are mapped in
/etc/dahdi/assigned-spans.conf the order of their startup is irrelevant:
the identification of channels attached to either serial
number or connector, and not to semi-random initialization order.

And this is why Asterisk could afford itself not to fail if DAHDI
channels are missing. Originally it failed because missing devices meant
that a device may be missing and thus existing channels may be
misplaced.

With a recent enough version of Asterisk, and with
ignore_failed_channels = true in chan_dahdi.conf (the default as of 13.
Makes sense also if you only have a single DAHDI device to begin with)
Asterisk will not fail if channels are missing: they wil just come
later. And indeed Asterisk can now allow DAHDI channels to be created
after initialization, and thus Asterisk does not need to wait for all
DAHDI devices to initialize before starting.

(This is not specific to Xorcom hardware and should generally apply to
any DAHDI hardware. I'm not exactly sure how this interacts with dynamic
spans and interested to hear reports, probably in a different thread)

-- 
               Tzafrir Cohen
icq#16849755              jabber:tzafrir.cohen at xorcom.com
+972-50-7952406           mailto:tzafrir.cohen at xorcom.com
http://www.xorcom.com