[SR-Users] Cleanup location table on failed NAT ping

[Daniel-Constantin Mierla]

Hello,

On 7/24/12 11:47 PM, David wrote:
> Hello,
>
> I am using kamailio 3.2.3.
>
> I am using the nathelper module to "ping" users in the location table 
> to keep the NAT bindings alive.
>
> In the event of 3 failed NAT pings, I would like to mark the entry as 
> "unavailable" or completely delete it from the location table to avoid 
> having stale data.
>
> Is this a feature that exists ? Is not, are their plans for it in the 
> future ?
>
> When the REGISTER expires after 3600, if the phone doesn't register, 
> the location entry gets cleaned up. So I have to wait up to one hour 
> before the bad entry is purged. I was hoping to have it purged sooner.

auto-unregister on nat keepalives timeout does not exist -- actually the 
nat keepalive si a simply udp send (even for OPTIONS) for performance 
reasons, there is no transaction created for it, the reply is handled 
stateless by core and discarded due to single Via header.

I think it can be implemented by using an external tool to send the 
keepalives, like sipsak, and by using a failure route for them, in the 
case of timeout, one can call unregister() -- this would work if there 
is one contact per subscriber.

Regarding the development of such feature, I don't have it in my short 
terms plans and I am not aware of anyone else working on it, but maybe 
other developers can comment on that.

 From my point of view, it will not bring significant benefits, but can 
add lot of load to tm for handling keepalive transactions when dealing 
with large number of location records.

Cheers,
Daniel

-- 
Daniel-Constantin Mierla - http://www.asipto.com
http://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda
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