Number 0Nxxxxxxx is currently OFFLINE

This is something that's been bugging me for a little while with my iax2 trunk to 2talk. Fundamentally I'm just a bit sow to get how it all hangs together. Generally it works out of the box so I don't 'need' to understand it to use it ... except it's good to know how it hangs together when things get weird.

That said some kind of recent change (possibly with 2talk plus account set-up) my registration died and 2talk showed me as 'OFFLINE' .. hmm.

*CLI> iax2 show registry
Host                  dnsmgr  Username    Perceived             Refresh  State
202.180.76.166:4569   N       0Nxxxxxx               60  Timeout
202.180.76.166:4569   N       0Nxxxxxx               60  Timeout

Ok so I'm not registered - but, I can make outbound calls ... odd? No - this is a clear description:

The only purpose of registration is to allow a device to identify its location on the network, so that Asterisk knows where to send calls intended for that device.

Thank you Mr O'Reilly http://ofps.oreilly.com/titles/9780596517342/asterisk-DeviceConfig.html

OK so I didn't change anything so perhaps I can force a registry reset / refresh, etc 

*CLI> iax2 unregister
Usage: iax2 unregister
       Unregister (force expiration) an IAX2 peer from the registry.

Hmm .. not helpful - I can't figure out what the peername is .. a few attempts from iax2 show peers to get the name don't seem to help. So I default to a fallback option - change the registry string to something wrong, reload asterisk, then change in back .. maybe. 

So I choose (rather fortuitously)  to replace:

0Nxxxxxx:@iax.2talk.co.nz 

with

0Nxxxxxx:@iax.plus.2talk.co.nz 

and  guess what, it works .. well maybe a change to the 2talk+ accounts? I can't find a reference say here http://blog.2talk.co.nz/iax2.html or  here http://www.2talk.co.nz/2talkplus/ . I've created a ticket so will see what they say.

*UPDATE* apparently if you're on 2talk+ you should always use .plus .. so looks like the last related change got pushed through and they've stopped supporting registration on the old domain. OK.