[cisco-nas] Modems not responding on cisco AS5300.

[Aaron Leonard]

>> From the debugs, it looks like this call into modem 2/51 simply failed
>> to train.  It is possible that the DSP that handles 2/51 (and 2/50) has
>> gone into some bad state; can't tell from the debugs alone.
>>     
>
> Yeah. If you're calling it on the phone when this issue occurs, you see that 
> in the debug logs but what you hear on the phone is just dead air. No modem, 
> nothing.
>   

Good test - then I definitely go with the dead DSP theory.

> Thanks for the suggestions, I'll try them and report what happens.
>   

There's one more thing you can do - hunt down the client modem that is
putting the DSP into the bad state.

I.e. look at your modem logs and find out who had last called right
before the DSP went into the bad state.  (Here I assume that you are
getting CLID from the switch.)  There may be a pattern - you may see the
same CLID popping up over and over again when the DSP goes bad.  If you
can figure out who this is, you can offer them a free modem if they stop
calling you with this one.  (Don't laugh, we have had some other
customers employ this technique successfully.)

Aaron