[Asterisk-Users] Intermittent breakage with the ISDN4Linux modem driver

[Steve Hill]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1


I'm having some problems using the asterisk modem driver with an 
ISDN4Linux card (AVM Fritz).  (I realise that it's better to use CAPI, 
but unfortunately this card doesn't have any CAPI drivers).

Every so often the ISDN just stops working (it neither dials out nor 
accepts incoming calls).  Trying to dial out just logs:
     -- Executing Dial("IAX2/steve at steve/1", "Modem/g1/48:19") in new stack
and then sits there.

If a call comes in, the kernel logs:
 	isdn_net: call from 19 -> 0 41 ignored
 	isdn_tty: call from 19, -> RING on ttyI0
But Asterisk doesn't log anything at all.

Anything not going through the ISDN keeps working just fine.

I _think_ this is only happening after an outgoing call hangs up (the 
incoming calls seem to be fine).  Also, on an outgoing call, if the phone 
on the PSTN side of the ISDN hangs up Asterisk doesn't seem to notice the 
hangup so this is probably related.

If you try to shut down Asterisk using "stop now" or "restart now" 
when it is in this state, then it sometimes doesn't shut down and the 
only thing you can do is "killall -9 asterisk".  If it does shut down you 
get:
 	Beginning asterisk shutdown....
 	Executing last minute cleanups
 	  == Destroying any remaining musiconhold processes
 	Asterisk uncleanly ending (2).

Oddly, if I turn on debugging then it *always* hangs the whole 
Asterisk process upon ISDN hangup, logging:

Jan 21 10:00:01 DEBUG[15733]: chan_modem_i4l.c:413 i4l_read: Value of 
escape is ^ (3)...
Jan 21 10:00:01 DEBUG[15733]: chan_modem_i4l.c:242 i4l_handle_escape: 
Escaped character '<some extended ASCII character>'
Jan 21 10:00:01 NOTICE[15733]: channel.c:1691 
ast_set_write_format: Unable to find a path from unknown to slin
Jan 21 10:00:01 DEBUG[15733]: channel.c:739 ast_hangup: Hanging up channel 
'Modem[i4l]/ttyI0'
Jan 21 10:00:01 DEBUG[15733]: chan_modem.c:423 modem_hangup: 
modem_hangup(Modem[i4l]/ttyI0)
Jan 21 10:00:01 DEBUG[15733]: chan_modem_i4l.c:154 i4l_init: i4l_init()

And help would be appreciated - thank you.

  - Steve       Jabber: steve at nexusuk.org     Web: http://www.nexusuk.org/

      Servatis a periculum, servatis a maleficum - Whisper, Evanescence

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.6 (GNU/Linux)
Comment: Public key available at http://www.nexusuk.org/pubkey.txt

iD8DBQFB8Naa5zUOsIV3bqERAql1AJ9fLjCWsvuMEt07dVFk4YyKVTrEjwCfWgNf
MCbJjoAAV0atHnajNoAapPs=
=Vfst
-----END PGP SIGNATURE-----