T2 flapping a lot

[melozurdo]

Hi guys,

I am getting these messages with a high frequency in the PBX I support.

28/11/18 09:43:40 001004M|002/06/0/000|=2:0310=T2 Dlap Released
28/11/18 09:43:40 001004M|002/06/0/000|=4:2113=T2 LAPD not established still trying
28/11/18 09:43:40 001004M|002/06/0/000|=3:2825=PH: Access (2 6 0) goes down
28/11/18 09:43:46 001004M|002/06/0/000|=5:0311=T2 Dlap Established
28/11/18 09:43:46 001004M|002/06/0/000|=5:2836=PH: Access (2 6 0) is up

I think it could be related with cable or card hardware issue but want to confirm with you.
If yes, how can i try to fix this? Restart the coupler with rstcpl command? OR maybe double bascul? Thre PBX have 2 CPUs. Thanks.

Regards,
Nacho

[vad]

You can have problem with synchronization (check with "infocs" command)
You can have problem with transmission equipment (modem, MUX...)
You can have problem with remote site.....

With trkstat 2 6 - what about AIS, RAI, NOS error?

Usually board restart or PBX restart not help you.

[melozurdo]

infocs output:

+----------------------------------------------------------------------+
| N_CR | N_CPL | TYPE | N_ACCES | PRIO | SYNC_CLOCK | TG/LK |
+----------------------------------------------------------------------+
+----------------------------------------------------------------------+

+---------------------------------------------------------------------+
| Synchronization on global domain |
+---------------------------------------------------------------------+
+---------------------------------------------------------------------+
| Synchronization on domain no 2 |
+---------------------------------------------------------------------+
| N_CR | N_CPL | TYPE | N_ACCES | PRIO | SYNC_CLOCK | TG/LK |
+---------------------------------------------------------------------+
| 2 | 6 | PRA T1 | 0 | 201 | SYNCHRO | TG:400 |
+---------------------------------------------------------------------+


+========================== Synchro DECT ==================================+

+--------------------------------------------------------------------------+
| N_CR | N_CPL | TYPE | DECT_CLOCK | Depending Crystals |
+--------------------------------------------------------------------------+
+--------------------------------------------------------------------------+


+========= campus synchronization via INTOFS ====================+

this node 4 is SLAVE of campus synchronization (master node = ?)
synchro = PHASE_NO_OPERATION (phase shift values = 0,0)
info1=0 info2=0 info3=0 info4=0

trkstat 2 6 output:

+------------------------------------------------------------------------------+
| T R U N K S T A T E - PRA T Coupler Crystal_nbr = 2 |
| IN SERVICE Coupler Nbr = 6 |
+------------------------------------------------------------------------------+
| Type : T1 CCS Access 0 : ENABLED level2 : CONNECT2 |
| B channel rate : 64K |
| |
| Trunk Grp 400 400 400 400 400 400 400 400 400 400 400 400 |
| Channel 1 2 3 4 5 6 7 8 9 10 11 12 |
| State F F B F F F F B F F F F |
| |
| Trunk Grp 400 400 400 400 400 400 400 400 400 400 400 |
| Channel 13 14 15 16 17 18 19 20 21 22 23 |
| State F F F F F F F F F F F |
| |
| Trunk Grp |
| Channel |
| State |
+------------------------------------------------------------------------------+
| F: Free | B: Busy | Ct: busy Comp trunk | Cl: busy Comp link |
| WB: Busy Without B Channel| Cr: busy Comp trunk for RLIO inter-ACT link |
| WBD: Data Transparency without chan.| WBM: Modem transparency without chan. |
| D: Data Transparency | M: Modem transparency |
+------------------------------------------------------------------------------+
| ALARM COUNTERS |
+------------------------------------------------------------------------------+
| LMFA | RAI | LFA | AIS | LOS | MIC_LOOP |
| 0 | 26 | 89 | 8 | 3 | 0 |
|------------------------------------------------------------------------------|
| LMFA : Loss of Multi Frame Alignement | RAI : Remote Alarm Indication |
| LFA : Loss of Frame Alignement | AIS : Alarm Indication signal |
| LOS : Loss Of Signal | |
+------------------------------------------------------------------------------+

I issued trkstat 2 6 command several times and alarm counters are not changing. Please advise.

[vad]

"I issued trkstat 2 6 command several times and alarm counters are not changing." - Alarm counters are not changing but what about incidents "2:0310=T2 Dlap Released" (between trkstat command entering)? Alarms interesting for us if problem still exist (AIS - usually problem between your PBX and provider, RAI - provider have problem with signal from your, NOS - you have problem with signal from provider).
infocs show - you manage synchronization from T1. But what about remote site and equipment between (modems, MUX)?

[melozurdo]

"I issued trkstat 2 6 command several times and alarm counters are not changing." - Alarm counters are not changing but what about incidents "2:0310=T2 Dlap Released" (between trkstat command entering)? Alarms interesting for us if problem still exist (AIS - usually problem between your PBX and provider, RAI - provider have problem with signal from your, NOS - you have problem with signal from provider).
infocs show - you manage synchronization from T1. But what about remote site and equipment between (modems, MUX)?

Hi,

Problem still exist but the AIS, RAI and LOS values are the same (not changing). Here is the log for today:

30/11/18 08:35:10 001004M|002/06/0/000|=2:0310=T2 Dlap Released
30/11/18 08:35:10 001004M|002/06/0/000|=4:2113=T2 LAPD not established still trying
30/11/18 08:35:10 001004M|002/06/0/000|=3:2825=PH: Access (2 6 0) goes down
30/11/18 08:35:17 001004M|002/06/0/000|=5:0311=T2 Dlap Established
30/11/18 08:35:17 001004M|002/06/0/000|=5:2836=PH: Access (2 6 0) is up
30/11/18 08:40:28 001004M|002/06/0/000|=2:0310=T2 Dlap Released
30/11/18 08:40:28 001004M|002/06/0/000|=4:2113=T2 LAPD not established still trying
30/11/18 08:40:28 001004M|002/06/0/000|=3:2825=PH: Access (2 6 0) goes down
30/11/18 08:40:34 001004M|002/06/0/000|=5:0311=T2 Dlap Established
30/11/18 08:40:34 001004M|002/06/0/000|=5:2836=PH: Access (2 6 0) is up
30/11/18 08:46:06 001004M|002/06/0/000|=2:0310=T2 Dlap Released
30/11/18 08:46:06 001004M|002/06/0/000|=4:2113=T2 LAPD not established still trying
30/11/18 08:46:06 001004M|002/06/0/000|=3:2825=PH: Access (2 6 0) goes down
30/11/18 08:46:12 001004M|002/06/0/000|=5:0311=T2 Dlap Established
30/11/18 08:46:12 001004M|002/06/0/000|=5:2836=PH: Access (2 6 0) is up
30/11/18 08:51:02 001004M|---/--/-/---|=3:1613=15.04.0d.00.02.02.82.20.80.ff.00.00.00.00.00
30/11/18 08:51:02 001004M|---/--/-/---|=3:1613=15.04.0d.00.02.02.85.12.60.ff.00.00.00.00.00
30/11/18 08:51:16 001004M|---/--/-/---|=3:1613=15.04.0d.00.02.02.85.12.60.ff.00.00.00.00.00
30/11/18 08:52:45 001004M|---/--/-/---|=3:1405=ABCA rout src 0 .1.-1
30/11/18 08:55:46 001004M|002/03/0/015|=5:2053=Terminal 15 in service
30/11/18 09:01:22 001004M|002/06/0/000|=2:0310=T2 Dlap Released
30/11/18 09:01:22 001004M|002/06/0/000|=4:2113=T2 LAPD not established still trying
30/11/18 09:01:22 001004M|002/06/0/000|=3:2825=PH: Access (2 6 0) goes down
30/11/18 09:01:28 001004M|002/06/0/000|=5:0311=T2 Dlap Established
30/11/18 09:01:28 001004M|002/06/0/000|=5:2836=PH: Access (2 6 0) is up

(104)xa001004> clock
Fri Nov 30 09:33:45 2018 -0.458692 seconds

****************

(104)xa001004> trkstat 2 6

Fri Nov 30 09:37:32 PST 2018
+------------------------------------------------------------------------------+
| T R U N K S T A T E - PRA T Coupler Crystal_nbr = 2 |
| IN SERVICE Coupler Nbr = 6 |
+------------------------------------------------------------------------------+
| Type : T1 CCS Access 0 : ENABLED level2 : CONNECT2 |
| B channel rate : 64K |
| |
| Trunk Grp 400 400 400 400 400 400 400 400 400 400 400 400 |
| Channel 1 2 3 4 5 6 7 8 9 10 11 12 |
| State F F F F F F F F F F F F |
| |
| Trunk Grp 400 400 400 400 400 400 400 400 400 400 400 |
| Channel 13 14 15 16 17 18 19 20 21 22 23 |
| State F F F F F B F F F F F |
| |
| Trunk Grp |
| Channel |
| State |
+------------------------------------------------------------------------------+
| F: Free | B: Busy | Ct: busy Comp trunk | Cl: busy Comp link |
| WB: Busy Without B Channel| Cr: busy Comp trunk for RLIO inter-ACT link |
| WBD: Data Transparency without chan.| WBM: Modem transparency without chan. |
| D: Data Transparency | M: Modem transparency |
+------------------------------------------------------------------------------+
| ALARM COUNTERS |
+------------------------------------------------------------------------------+
| LMFA | RAI | LFA | AIS | LOS | MIC_LOOP |
| 0 | 26 | 89 | 8 | 3 | 0 |
|------------------------------------------------------------------------------|
| LMFA : Loss of Multi Frame Alignement | RAI : Remote Alarm Indication |
| LFA : Loss of Frame Alignement | AIS : Alarm Indication signal |
| LOS : Loss Of Signal | |
+------------------------------------------------------------------------------+

The outage late around only 6 seconds so I don´t have time to issue "trkstat 2 6" when the T2 is down.
Also I don´t what you mean with "what about remote site and equipment between (modems, MUX)" ????
Another key point is when a call is placed, any of the card lights are ON...at least "busy" light should be ON when calls are in place.
Please advise. Thanks.

[vad]

"Also I don´t what you mean with "what about remote site and equipment between (modems, MUX)" ????"

Remote site - ask provider about problem with T1. May be problem on another side of link.

Modems/MUX - max cable length for T1 link ~300 m, so between PBX (site and provider) usually used some equipment - FO converters, modems.... Problem can be with this equipment.

"at least "busy" light should be ON when calls are in place." - yes.
If you have no Busy LED when calls in place:
- T1 board broken
- you are confusing the shelf number (disconnect patch-cord from T1 card - you will see in incidents - access 2-6 or another).

[melozurdo]

"Also I don´t what you mean with "what about remote site and equipment between (modems, MUX)" ????"

Remote site - ask provider about problem with T1. May be problem on another side of link.

Modems/MUX - max cable length for T1 link ~300 m, so between PBX (site and provider) usually used some equipment - FO converters, modems.... Problem can be with this equipment.

"at least "busy" light should be ON when calls are in place." - yes.
If you have no Busy LED when calls in place:
- T1 board broken
- you are confusing the shelf number (disconnect patch-cord from T1 card - you will see in incidents - access 2-6 or another).

Hi,
Onsite people sent a couple of pictures of the T1 board and the busy light is ON when a call is made. Also they checked the way betwwen PBX and provider and didn´t found a middle device between them. I asked them to reset the t1 cable so I am monitoring if we have more T1 bounces. I´ll let you know but having this data, it seems to be a telco provider issue, right?

[melozurdo]

"Also I don´t what you mean with "what about remote site and equipment between (modems, MUX)" ????"

Remote site - ask provider about problem with T1. May be problem on another side of link.

Modems/MUX - max cable length for T1 link ~300 m, so between PBX (site and provider) usually used some equipment - FO converters, modems.... Problem can be with this equipment.

"at least "busy" light should be ON when calls are in place." - yes.
If you have no Busy LED when calls in place:
- T1 board broken
- you are confusing the shelf number (disconnect patch-cord from T1 card - you will see in incidents - access 2-6 or another).

Hi,
Onsite people sent a couple of pictures of the T1 board and the busy light is ON when a call is made. Also they checked the way betwwen PBX and provider and didn´t found a middle device between them. I asked them to reset the t1 cable so I am monitoring if we have more T1 bounces. I´ll let you know but having this data, it seems to be a telco provider issue, right?

Problem is still present even being reset T1 cable. Now the values in trkstat 2 6 are the following:

+------------------------------------------------------------------------------+
| T R U N K S T A T E - PRA T Coupler Crystal_nbr = 2 |
| IN SERVICE Coupler Nbr = 6 |
+------------------------------------------------------------------------------+
| Type : T1 CCS Access 0 : ENABLED level2 : CONNECT2 |
| B channel rate : 64K |
| |
| Trunk Grp 400 400 400 400 400 400 400 400 400 400 400 400 |
| Channel 1 2 3 4 5 6 7 8 9 10 11 12 |
| State F F F F F B F F F F F F |
| |
| Trunk Grp 400 400 400 400 400 400 400 400 400 400 400 |
| Channel 13 14 15 16 17 18 19 20 21 22 23 |
| State F F F F F F F F F F F |
| |
| Trunk Grp |
| Channel |
| State |
+------------------------------------------------------------------------------+
| F: Free | B: Busy | Ct: busy Comp trunk | Cl: busy Comp link |
| WB: Busy Without B Channel| Cr: busy Comp trunk for RLIO inter-ACT link |
| WBD: Data Transparency without chan.| WBM: Modem transparency without chan. |
| D: Data Transparency | M: Modem transparency |
+------------------------------------------------------------------------------+
| ALARM COUNTERS |
+------------------------------------------------------------------------------+
| LMFA | RAI | LFA | AIS | LOS | MIC_LOOP |
| 0 | 47 | 99 | 12 | 4 | 0 |
|------------------------------------------------------------------------------|
| LMFA : Loss of Multi Frame Alignement | RAI : Remote Alarm Indication |
| LFA : Loss of Frame Alignement | AIS : Alarm Indication signal |
| LOS : Loss Of Signal | |
+------------------------------------------------------------------------------+

It sounds a telco provider issue, right?

[tot3nkopf]

Try to play with line attenuation. You have several values (I think in digital access' e.g. short line, long line, etc.)

[melozurdo]

Try to play with line attenuation. You have several values (I think in digital access' e.g. short line, long line, etc.)

After opening several ticket with telco provider and have had trunk channels in "hs" status, now the trunk is OK but still having T1 circuit bounces.
Also LFA values have increased:

+------------------------------------------------------------------------------+
| ALARM COUNTERS |
+------------------------------------------------------------------------------+
| LMFA | RAI | LFA | AIS | LOS | MIC_LOOP |
| 0 | 65 | 235 | 27 | 4 | 0 |
|------------------------------------------------------------------------------|
| LMFA : Loss of Multi Frame Alignement | RAI : Remote Alarm Indication |
| LFA : Loss of Frame Alignement | AIS : Alarm Indication signal |
| LOS : Loss Of Signal | |

Logs for today...

06/12/18 03:59:48 001004M|002/06/0/000|=2:0310=T2 Dlap Released
06/12/18 03:59:48 001004M|002/06/0/000|=4:2113=T2 LAPD not established still trying
06/12/18 03:59:48 001004M|002/06/0/000|=3:2825=PH: Access (2 6 0) goes down
06/12/18 03:59:54 001004M|002/06/0/000|=5:0311=T2 Dlap Established
06/12/18 03:59:54 001004M|002/06/0/000|=5:2836=PH: Access (2 6 0) is up
06/12/18 04:05:10 001004M|002/06/0/000|=2:0310=T2 Dlap Released
06/12/18 04:05:10 001004M|002/06/0/000|=4:2113=T2 LAPD not established still trying
06/12/18 04:05:10 001004M|002/06/0/000|=3:2825=PH: Access (2 6 0) goes down
06/12/18 04:05:17 001004M|002/06/0/000|=5:0311=T2 Dlap Established
06/12/18 04:05:17 001004M|002/06/0/000|=5:2836=PH: Access (2 6 0) is up

What do you mean with "Try to play with line attenuation" ?