Interesting problem with ISDN PRI

era_cisco · ‎03-04-2010

Hi everybody,

I got interesting issue with ISDN PRI.

Situation:

CISCO 3825/SRST/K9.

Two E1 ISDN PRI lines connected from telco, all 60 timeslots used, also 8 FXS for faxes.

120 IP Phones in this branch, all connected to central offce CUCM 6.0.

Signalling protocol between 3825 and CUCM is H.323. SRST is up.

Problem:

If i try more than 12 simulation calls using ISDN, no matter incoming or outgoing - 3825 got a message: "Temporary Failure" then disconnect session.

That is not like telco problem, becouse TX with disconnect going from 3825.

001447: *Mar 4 15:51:21: ISDN Se0/1/0:15 Q931: RX <- SETUP pd = 8 callref = 0x0006
                Bearer Capability i = 0x8090A3
                                Standard = CCITT
                                Transfer Capability = Speech
                                Transfer Mode = Circuit
                                Transfer Rate = 64 kbit/s
                Channel ID i = 0xA98392
                                Exclusive, Channel 18
                Progress Ind i = 0x8183 - Origination address is non-ISDN
                Calling Party Number i = 0x2181, '4953639610'
                                Plan:ISDN, Type:National
                Called Party Number i = 0x81, '3639688'
                                Plan:ISDN, Type:Unknown
                Sending Complete
001448: *Mar 4 15:51:21: ISDN Se0/1/0:15 Q931: Received SETUP callref = 0x8006 callID = 0x0011 switch = primary-net5 interface = User
001449: *Mar 4 15:51:21: ISDN Se0/1/0:15 Q931: TX -> CALL_PROC pd = 8 callref = 0x8006
                Channel ID i = 0xA98392
                                Exclusive, Channel 18
001450: *Mar 4 15:51:21: ISDN Se0/0/0:15 Q931: RX <- PROGRESS pd = 8 callref = 0x808F
                Progress Ind i = 0x8A88 - In-band info or appropriate now available
001451: *Mar 4 15:51:21: ISDN Se0/1/0:15 Q931: TX -> ALERTING pd = 8 callref = 0x8006
                Progress Ind i = 0x8188 - In-band info or appropriate now available
001452: *Mar 4 15:51:21: ISDN Se0/0/0:15 Q931: RX <- ALERTING pd = 8 callref = 0x808F
                Progress Ind i = 0x8A88 - In-band info or appropriate now available
001453: *Mar 4 15:51:25: ISDN Se0/0/0:15 Q931: TX -> DISCONNECT pd = 8 callref = 0x008F
                Cause i = 0x80A9 - Temporary failure
001454: *Mar 4 15:51:25: ISDN Se0/0/0:15 Q931: RX <- RELEASE pd = 8 callref = 0x808F
                Cause i = 0x80A9 - Temporary failure

What I did:

- Change IOS, from default box 12.4.15T, to 12.4.22T, then to 12.4.24T2. Error still remain.

- Change PVDM. Error still remain.

Config is typical, working with 99 percent of all local operators.

In attach - show run and show debug.

May be it cause by defect E1 cards?

Has anyone face this issue before?

Thanks for answer.

Yaroslav Muraviev.

paolo bevilacqua · ‎03-05-2010

It is a problem with CM, if you was to debug h323 you would see the disconnect comes from there.

So you have to troubleshoot on CM, not router.

iantra123 · ‎03-05-2010

The conf is OK.

Check the "show voice dsp group all", verify if all is OK.

Remove the first E1 cards and the FXS, and then try to make calls with one E1 card . Test them one by one.

The error may be at the first E1 card because it is in the first preference. I already experience this.