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Bug #2731

OpenBSC doesn't release lchan if MSC does a hard SCCP disconnect

Added by laforge about 1 month ago. Updated 14 days ago.

Status:
New
Priority:
Normal
Assignee:
Category:
-
Target version:
-
Start date:
12/09/2017
Due date:
% Done:

0%

Spec Reference:

Description

When the MSC doesn't follow normal procedure of ClearCommand but simply hard disconnects the SCCP connection (such as possible in any number of failure scenarios), we are not clearing the lchan / radio channel:

<000a> osmo_bsc_sigtran.c:258 Initializing resources for new SIGTRAN connection to MSC: RI=SSN_PC,PC=0.23.1,SSN=BSSAP,GTI=NO_GT...
<000a> osmo_bsc_sigtran.c:287 Allocated new connection id: 27
<000a> osmo_bsc_sigtran.c:315 Opening new SIGTRAN connection (id=27) to MSC: RI=SSN_PC,PC=0.23.1,SSN=BSSAP,GTI=NO_GT
<001a> osmo_bsc_sigtran.c:196 N-CONNECT.cnf(27)
<001a> osmo_bsc_sigtran.c:220 N-DISCONNECT.ind(27, cause=768)
<000a> osmo_bsc_sigtran.c:381 sccp connection (id=27) not cleared (gsm subscriber connection still active) -- forcefully clearing it now!
<0005> bsc_api.c:291 The lchan should have been cleared.

OsmoBSC> show lchan 
BTS 0, TRX 0, Timeslot 1, Lchan 0: Type TCH_F
  Connection: 0, State: ACTIVE
  BS Power: 3 dBm, MS Power: 16 dBm
  Channel Mode / Codec: signalling
  No Subscriber
  Bound IP: 0.0.0.0 Port 0 RTP_TYPE2=0 CONN_ID=0
  Measurement Report:
    Flags: DLinval 
    RXL-FULL-ul: -110 dBm, RXL-SUB-ul: -110 dBm RXQ-FULL-ul: 0, RXQ-SUB-ul: 0

I'm adding testcase TC_chan_rel_hard_rlsd about this to the BSC_Tests TTCN-3 testuite.


Related issues

Related to OsmoBSC - Bug #2726: OsmoBSC doesn't release lchan if MSC refuses connection (CR -> CREF) New 12/08/2017

History

#1 Updated by laforge about 1 month ago

  • Related to Bug #2726: OsmoBSC doesn't release lchan if MSC refuses connection (CR -> CREF) added

#2 Updated by laforge 14 days ago

  • Assignee set to dexter

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