[VoIP] Unknown problem ?

[Rusty Dekema]

On 8/13/07, Greg Blakely <greg at vyger.net> wrote:
> If you have either your sip or iax2 clients tagged as anything other
> than QUALIFY=NO, then asterisk will check them on a continual basis to
> see if they are reachable.  If they're not, then calls won't even be
> attempted to them.
>
> You'll also get notice on the console when reachable/unreachable status
> changes.

In my experience running Asterisk 1.2, the qualify feature was
absolutely useless. SIP devices (of all kinds; various softphones,
hardware-based ATAs, etc) would habitually "flap" back and forth from
reachable to unreachable even though they were connected to my
Asterisk server on a completely non-loaded 100mbit local ethernet,
even though the Asterisk server and the PCs running the soft phones
had no other CPU load, and even though I increased the qualify= time
to over 2000ms.

Since these SIP devices otherwise worked perfectly, it was quite clear
that they were not truly "unreachable" for periods approaching
anything like 2 seconds. I don't know what the problem was, and I
don't know whether it still exists in Asterisk 1.4 since, although I
run it, I have not bothered to turn the qualify option back on.

Rusty