Cisco ISR 4431 PRI issues

[mariodavila1]

Looking for assistance with our PRIs connected to Cisco ISR 4431, Cisco IOS XE Software, Version 16.04.01.

We are connecting via PRI to local vendor for local/incoming and outgoing (2 way) service.

Calls are working correctly but every so often (which makes this harder to catch) we will receive a "fast busy/all trunks busy" indication. When I debug the calls, looks like channel is not available. Seems as if the calls are giving false status indication.

Or not totally releasing from previous call. If I bump the port via cli in the router, it will clear up and return to normal service...until the next time. Our other circuits attached to Cisco 2951 (older) do NOT seem to have these issues...ever!

I suspect there is a bug. Has anyone had these issues? I'd like to research this issue for a fix action. DSP allocation is fine.

Thanks in advance. Maybe just tell me where to look for guide that provide line break down so I can decipher the errors being shown.

see example:

121406173: Apr 15 16:03:07.209: ISDN Se0/2/3:23 Q931: SETUP pd = 8 callref = 0x0DFC
Bearer Capability i = 0x8090A2
Standard = CCITT
Transfer Capability = Speech
Transfer Mode = Circuit
Transfer Rate = 64 kbit/s
Channel ID i = 0xA98397
Exclusive, Channel 23
Facility i = 0x9F8B0100A10F02017006072A8648CE1500040A0100
Protocol Profile = Networking Extensions
0xA10F02017006072A8648CE1500040A0100
Component = Invoke component
Invoke Id = 112
Operation = InformationFollowing (calling_name)
Name information in subsequent FACILITY message
Progress Ind i = 0x8281 - Call not end-to-end ISDN, may have in-band info
Calling Party Number i = 0x2183, '512XXXXXXX'
Plan:ISDN, Type:National
Called Party Number i = 0xC1, '56XXXXX'
Plan:ISDN, Type:Subscriber(local)
121406174: Apr 15 16:03:07.209:
cmbrl_send_pak: --> Sending backhauled msg for Se0/2/3:23 :
| bk_msg_type = DATA_IND
| bk_chan_id (slot:port) = 0:3
| Q.931 length = 66
| Q.931 message type: SETUP
| Q.931 message = 08020DFC0504038090A21803A983971C159F8B0100A10F02017006072A8648CE1500040A01001E0282816C0C2183353132353339383530307008C135363530313032
121406175: Apr 15 16:03:07.211: ISDN Se0/2/3:23 Q921: User TX -> RR sapi=0 tei=0 nr=10
121406176: Apr 15 16:03:07.212:
cmbh_rcv_callback: <-- Receiving backhaul msg for Se0/2/3:23 :
| bk_msg_type = DATA_REQ
| bk_chan_id (slot:port) = 0:3
| Q.931 length = 9
| Q.931 message type: RELEASE COMPLETE
| Q.931 message = 08028DFC5A080280AC
121406177: Apr 15 16:03:07.212: ISDN Se0/2/3:23 Q921: User TX -> INFO sapi=0 tei=0, ns=67 nr=10
121406178: Apr 15 16:03:07.212: ISDN Se0/2/3:23 Q931: RELEASE_COMP pd = 8 callref = 0x8DFC
Cause i = 0x80AC - Requested circuit/channel not available

NUMBER BLOCKED FOR PRIVACY. XXXXXXX

[Mohammed al Baqari]

Hi,

You need to check with your telco as they aren't releasing the call. Its
either all the channels are engaged or the provider circuit is having
problems and not able to establish the message.

[mariodavila1]

Thanks, that is a good point. I thought that as well but some of the PRIs are connected to a different switch all together and they are also having calls when initiating calls. Strange issue because the same circuit will pass traffic and then fail the next time. I suspect there might be a bug in the 4431. Appreciate the input! Oh, I think I mentioned that same setup on diggerent gateway, 2951, NEVER fails and all circuits are created the same. The plot thickens. :)

[Aman Soi]

Hi,

not sure but there is a bug related to memory leaks for ISDN

ISDN memory still leaks with fix in CSCvh73134

CSCvn37161

Description

Symptom:
Voice gateway router running IOS-XE may experience ISDN memory leak#show processes memory 595
Tracekey : 1#2d1938daae461abf1215018b489ca21b  
Process ID: 595
Process Name: ISDN
Total Memory Held: 75773440 bytes   <<<<<<<<<<<<<<<<<

Processor memory Holding = 75773440 bytes
size =  74713776, count = 313018, pc = :55DCC2D9D000+7C6472E
size =    389608, count = 1956, pc = :55DCC2D9D000+7BAD511
size =    148224, count =    8, pc = :55DCC2D9D000+7B7E7FA

Conditions:
ISDN calls


#show memory debug leaks
Tracekey : 1#2d1938daae461abf1215018b489ca21b   Workaround:
reload to reclaim memory.

[mariodavila1]

Thank you, I'll check it out. Appreciate you guys.

[Mohammed al Baqari]

Hi Amon,

FYI, memory leak will cause admission control error message. But in this
case we are getting no circuit available as rx from telco.