[asterisk-dev] [Code Review] Patch for issue 12312 (DNS SRV lookups causing re-registration problems)

[Mark Michelson]

Johansson Olle E wrote:
> Mark,
> It looks good.
> 
> As an addition, I think we should check the result of sip_do_register  
> in sip_reregister. If the xmit fails, which the result of that  
> function indicates, we should look up another server in SRV also and  
> stop using the first.
> 
> Make sure that the tags are reset when switching server.
> 
> If we fix this in 1.4, we should propably check if this addtional step  
> is needed in 1.4 or only in trunk.
> 
> /O

The patch I placed on reviewboard is very similar to what trunk already has in 
it, at least with regards to when and why we perform SRV lookups. Asterisk 
trunk's dnsmgr code has SRV-specific sections to it that are not in 1.4, so I 
could not use dnsmgr the same way it is used in trunk.

As far as SIP-specific actions to take when we switch IPs, I'm fairly certain 
that 1.4 and trunk are in parallel once this patch is applied, so if something 
needs to be updated further in 1.4, then trunk would need the same treatment. 
With regards to tags in particular, I will investigate under which circumstances 
we do and do not update our local tag. It's clear that in most cases we already 
have logic in place to change our tag, but it may not be covered under all 
failure cases.

Mark Michelson