[asterisk-users] Dropped Calls

[Brent Davidson]

On 3/30/2010 3:14 PM, Danny Nicholas wrote:
> A few thoughts;
> 1. I assume that the * servers aren't on dedicated networks;  Do the dropped
> or one-way calls occur during high-traffic times or are they concurrent with
> large downloads?  In my shop, we had to get a router that would prioritize
> voice traffic or we would be dead in the water during client file
> transmissions.
>    
Asterisk servers are not on a dedicated network, but our total network 
utilization is less than 10% max at any time.

> 2. Don't know about the SNOM or GS phones, but my Polycom phones let you
> establish higher packet priorities for voice traffic as well.
>    
I have all the phones, the asterisk server and the core switch set to 
prioritize RTP and SIP packets at top priority.  But I never see any 
indication of dropped or delayed packets in the logs.
> 3. Have you been able to do a "top" during one of these failures?  Could be
> a memory leak that comes up randomly.
>    
This one is a tough one.  When these types of calls occur it is 
completely random.  Sometimes there will be one or two in a row, other 
times there won't be one for a couple of days.  It would take some some 
serious logging to catch top data at the exact moment one of the calls 
drops or the one-way audio hits.
> 4. Looking at the startup logs, are the cards having to retry several times
> to get an IRQ?  Digium cards IME can conflict with the Hard Drive (SCSI)
> controller, causing problems during heavy I/O periods.
> Hope this helps
Cards all get an IRQ on the first try.

Other data of interest:  Our main office only has 8 incoming analog 
lines, the other offices all only have 2 incoming lines, and there is no 
correlation between calls in progress and and either of the problems.  
Sometimes the main office will have two or three in-progress calls and 
another incoming or outgoing call will experience one-way audio or a 
disconnect and the others are unaffected.  Not even a glitch in the 
audio.  I have had both problems happen to me after hours when I was the 
only one in the office so the network was completely idle and my call 
was the only one active.

I've been trying to trace this problem for about two years and still 
have not been able to make any real progress.  I guess I should just 
update to Dahdi and Asterisk 1.6, but I just hate to change a system 
that is (mostly) working.