We installed a fractional PRI in a site using h323. Everything seems to be working correctly most of the time until some of the users began complaining that they were unable to receive calls inbound on their phones at random parts of the day...
When troubleshooting using 'debug ISDN q931' I found that the calls were being rejected when the controller tried to use the channels 17 - 31 on the serial interface (see output below):
Apr 15 10:46:21 UTC: ISDN Se1/1:15 Q931: Received SETUP callref = 0x809C callID = 0x00F5 switch = primary-net5 interface = User
Apr 15 10:46:21 gmt: %ISDN-6-CHAN_UNAVAILABLE: Interface Se1/1:15 Requested Channel 17 is not available
Apr 15 10:46:21 UTC: ISDN Se1/1:15 **ERROR**: CCPMSG_InCall: ChannelID IE invalid 44(0x2C) rejecting call
Apr 15 10:46:21 UTC: ISDN Se1/1:15 Q931: TX -> RELEASE_COMP pd = 8 callref = 0x809C
Cause i = 0x80AC18 - Requested circuit/channel not available
Apr 15 10:46:41 UTC: ISDN Se1/1:15 Q931: RX <- SETUP pd = 8 callref = 0x003E
Bearer Capability i = 0x8090A3
Standard = CCITT
Transfer Capability = Speech
Transfer Mode = Circuit
Transfer Rate = 64 kbit/s
Channel ID i = 0xA98392
Exclusive, Channel 18
Calling Party Number i = 0x1083, '353879911644'
Called Party Number i = 0x81, '4495'
when I make another call the controller tries to use the next channel and will fail if it is between 17 and 31. As soon as it goes back down to channel 1 - 16, it works fine again. Can anyone help me out here. Is there a way to stop using the channels 17-31 and just use channels 1-16?
Would appreciate help on this as I dont want to open a TAC case,