Hello there,
In my lab I have access to an ip.access nanoBTS 165AU which I have setup with OsmoBSC. Sending SMS between my two test handsets (Nokia 105) are working fine, however it seems there is a problem when making calls. From the logs it seems the radio is unable to assign a TCH_F channel.
Any idea what could be causing this and how I would debug this further?
Cheers, Sebastian
<0003> abis_rsl.c:1533 (bts=0) CHAN RQD: reason: call re-establishment (ra=0x49, neci=0x01, chreq_reason=0x02) <000f> lchan_select.c:262 lchan(0-0-0-CCCH_SDCCH4-0)[0xaaaadc4251c0]{UNUSED}: (type=SDCCH) Selected <000f> lchan_fsm.c:636 lchan(0-0-0-CCCH_SDCCH4-0)[0xaaaadc4251c0]{WAIT_TS_READY}: (type=SDCCH) Activation requested: FOR_MS_CHANNEL_REQUEST voice=no MGW-ci=none type=SDCCH tch-mode=SIGNALLING encr-alg=A5/0 ck=none <0007> osmo_bsc_sigtran.c:297 Initializing resources for new SCCP connection to MSC 0: RI=SSN_PC,PC=0.23.1,SSN=BSSAP... <0007> osmo_bsc_sigtran.c:343 Opening new SCCP connection (id=4) to MSC 0: RI=SSN_PC,PC=0.23.1,SSN=BSSAP <0007> osmo_bsc_bssap.c:1147 Rx MSC DT1 BSSMAP COMMON ID <0007> osmo_bsc_bssap.c:1251 Rx MSC DTAP, SAPI: RR/MM/CC CHAN: 0 <0007> gsm_08_08.c:567 Tx MSC DTAP LINK_ID=0x00 <0007> osmo_bsc_sigtran.c:383 Tx MSC: DTAP <0007> osmo_bsc_bssap.c:1251 Rx MSC DTAP, SAPI: RR/MM/CC CHAN: 2 <0007> osmo_bsc_bssap.c:1110 Rx MSC UDT BSSMAP PAGING <0007> osmo_bsc_bssap.c:126 (msc0) Paging: subscr-IMSI-901700000050081-TMSI-0x06e8ff82: (bts0) Paging on LAC 1 <0007> osmo_bsc_bssap.c:1147 Rx MSC DT1 BSSMAP ASSIGNMENT REQ <000f> lchan_select.c:262 lchan(0-0-2-TCH_F-0)[0xaaaadc432ba0]{UNUSED}: (type=TCH_F) Selected <0011> assignment_fsm.c:570 assignment(msc0-conn4_subscr-IMSI-901700000050080-TMSI-0xbf4aa84d_0-0-2-TCH_F-0)[0xaaaadc43e930]{WAIT_LCHAN_ACTIVE}: (bts=0,trx=0,ts=2,ss=0) Starting Assignment: chan_mode=SPEECH_V1, chan_type=FR, aoip=yes MSC-rtp=192.168.148.159:4074 (osmux=no) <000f> lchan_fsm.c:636 lchan(0-0-2-TCH_F-0)[0xaaaadc432ba0]{WAIT_TS_READY}: (type=TCH_F) Activation requested: FOR_ASSIGNMENT voice=yes MGW-ci=new type=TCH_F tch-mode=SPEECH_V1 encr-alg=A5/0 ck=none <000f> lchan_fsm.c:81 lchan(0-0-2-TCH_F-0)[0xaaaadc432ba0]{WAIT_RLL_RTP_ESTABLISH}: (type=TCH_F) lchan-rtp failure in state WAIT_IPACC_CRCX_ACK: Received NACK on IPACC CRCX <000f> lchan_fsm.c:81 lchan(0-0-2-TCH_F-0)[0xaaaadc432ba0]{WAIT_RLL_RTP_ESTABLISH}: (type=TCH_F) lchan allocation failed in state WAIT_RLL_RTP_ESTABLISH: Failed to setup RTP stream: LCHAN_EV_RTP_ERROR in state WAIT_RLL_RTP_ESTABLISH
<000f> lchan_fsm.c:116 lchan(0-0-2-TCH_F-0)[0xaaaadc432ba0]{WAIT_RLL_RTP_ESTABLISH}: (type=TCH_F) Signalling Assignment FSM of error (lchan allocation failed in state WAIT_RLL_RTP_ESTABLISH: Failed to setup RTP stream: LCHAN_EV_RTP_ERROR in state WAIT_RLL_RTP_ESTABLISH ) <0011> assignment_fsm.c:821 assignment(msc0-conn4_subscr-IMSI-901700000050080-TMSI-0xbf4aa84d_0-0-2-TCH_F-0)[0xaaaadc43e930]{WAIT_RR_ASS_COMPLETE}: (bts=0,trx=0,ts=2,ss=0) Assignment failed in state WAIT_RR_ASS_COMPLETE, cause RADIO INTERFACE MESSAGE FAILURE: Failed to activate lchan (bts=0,trx=0,ts=2,ss=0) <0007> osmo_bsc_sigtran.c:379 Tx MSC: BSSMAP: ASSIGNMENT FAIL <0011> assignment_fsm.c:148 assignment(msc0-conn4_subscr-IMSI-901700000050080-TMSI-0xbf4aa84d_0-0-2-TCH_F-0)[0xaaaadc43e930]{WAIT_RR_ASS_COMPLETE}: (bts=0,trx=0,ts=2,ss=0) Assignment failed <0007> osmo_bsc_bssap.c:1251 Rx MSC DTAP, SAPI: RR/MM/CC CHAN: 2 <0007> osmo_bsc_bssap.c:1147 Rx MSC DT1 BSSMAP CLEAR COMMAND <0007> osmo_bsc_sigtran.c:379 Tx MSC: BSSMAP: CLEAR COMPLETE <0005> paging.c:84 (bts=0) Going to send paging commands: subscr-IMSI-901700000050081-TMSI-0x06e8ff82 for ch. type 0 (attempt 0) <000f> gsm_04_08_rr.c:1021 lchan(0-0-0-CCCH_SDCCH4-0)[0xaaaadc4251c0]{WAIT_BEFORE_RF_RELEASE}: (type=SDCCH) Got data in non active state, discarding. <0005> paging.c:84 (bts=0) Going to send paging commands: subscr-IMSI-901700000050081-TMSI-0x06e8ff82 for ch. type 0 (attempt 1) <0005> paging.c:84 (bts=0) Going to send paging commands: subscr-IMSI-901700000050081-TMSI-0x06e8ff82 for ch. type 0 (attempt 2) <0003> abis_rsl.c:1533 (bts=0) CHAN RQD: reason: answer to paging (ra=0x9f, neci=0x01, chreq_reason=0x01) <000f> lchan_select.c:262 lchan(0-0-0-CCCH_SDCCH4-1)[0xaaaadc425390]{UNUSED}: (type=SDCCH) Selected <000f> lchan_fsm.c:636 lchan(0-0-0-CCCH_SDCCH4-1)[0xaaaadc425390]{WAIT_TS_READY}: (type=SDCCH) Activation requested: FOR_MS_CHANNEL_REQUEST voice=no MGW-ci=none type=SDCCH tch-mode=SIGNALLING encr-alg=A5/0 ck=none <0005> paging.c:84 (bts=0) Going to send paging commands: subscr-IMSI-901700000050081-TMSI-0x06e8ff82 for ch. type 0 (attempt 3) <0007> osmo_bsc_sigtran.c:297 Initializing resources for new SCCP connection to MSC 0: RI=SSN_PC,PC=0.23.1,SSN=BSSAP... <0007> osmo_bsc_sigtran.c:343 Opening new SCCP connection (id=5) to MSC 0: RI=SSN_PC,PC=0.23.1,SSN=BSSAP <0007> osmo_bsc_bssap.c:1147 Rx MSC DT1 BSSMAP COMMON ID <0007> osmo_bsc_bssap.c:1147 Rx MSC DT1 BSSMAP CLEAR COMMAND <0007> osmo_bsc_sigtran.c:379 Tx MSC: BSSMAP: CLEAR COMPLETE <0003> abis_rsl.c:1533 (bts=0) CHAN RQD: reason: answer to paging (ra=0x88, neci=0x01, chreq_reason=0x01) <000f> lchan_select.c:262 lchan(0-0-0-CCCH_SDCCH4-0)[0xaaaadc4251c0]{UNUSED}: (type=SDCCH) Selected <000f> lchan_fsm.c:636 lchan(0-0-0-CCCH_SDCCH4-0)[0xaaaadc4251c0]{WAIT_TS_READY}: (type=SDCCH) Activation requested: FOR_MS_CHANNEL_REQUEST voice=no MGW-ci=none type=SDCCH tch-mode=SIGNALLING encr-alg=A5/0 ck=none <0007> osmo_bsc_sigtran.c:297 Initializing resources for new SCCP connection to MSC 0: RI=SSN_PC,PC=0.23.1,SSN=BSSAP... <0007> osmo_bsc_sigtran.c:343 Opening new SCCP connection (id=6) to MSC 0: RI=SSN_PC,PC=0.23.1,SSN=BSSAP <0007> osmo_bsc_bssap.c:1147 Rx MSC DT1 BSSMAP COMMON ID <0007> osmo_bsc_bssap.c:1147 Rx MSC DT1 BSSMAP CLEAR COMMAND <0007> osmo_bsc_sigtran.c:379 Tx MSC: BSSMAP: CLEAR COMPLETE
Hi,
On 7/30/21 4:49 PM, Sebastian Mauer wrote:
lchan(0-0-2-TCH_F-0)[0xaaaadc432ba0]{WAIT_RLL_RTP_ESTABLISH}: (type=TCH_F) lchan-rtp failure in state WAIT_IPACC_CRCX_ACK: Received NACK on IPACC CRCX
You received a IPACC CRCX NACK from nanoBTS as an answer to IPACC_CRCX (that's sent osmoBSc->nanoBTS to configure the RTP stream on the nanoBTS side). So it seems the nanoBTS is not liking the configuration you are requesting to it? Providing a pcap file containing Abis RSL would help understand better by looking at what the IPACC CRCX contains. I'd bet you are passing a loopback address to it or something similar, probably due to wrong osmo-mgw configuration.
Attached is a dump of the communication between BSC and nanoBTS when attempting to make a call. Thanks for helping with figuring this out.
Cheers, Sebastian
On Fri, 30 Jul 2021 at 16:13, Pau Espin Pedrol pespin@sysmocom.de wrote:
Hi,
On 7/30/21 4:49 PM, Sebastian Mauer wrote:
lchan(0-0-2-TCH_F-0)[0xaaaadc432ba0]{WAIT_RLL_RTP_ESTABLISH}: (type=TCH_F) lchan-rtp failure in state WAIT_IPACC_CRCX_ACK: Received NACK on IPACC CRCX
You received a IPACC CRCX NACK from nanoBTS as an answer to IPACC_CRCX (that's sent osmoBSc->nanoBTS to configure the RTP stream on the nanoBTS side). So it seems the nanoBTS is not liking the configuration you are requesting to it? Providing a pcap file containing Abis RSL would help understand better by looking at what the IPACC CRCX contains. I'd bet you are passing a loopback address to it or something similar, probably due to wrong osmo-mgw configuration.
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Nothing interesting can be said about your IPACC_CRCX message. Compare a pcap of a normal assignment, taken from our test suite: https://jenkins.osmocom.org/jenkins/view/TTCN3/job/ttcn3-bsc-test/lastSucces...
Maybe someone else knows whether it can be a problem with the nanoBTS configuration? I can't help with those devices unfortunately.
~N
On Fri, Jul 30, 2021 at 04:51:17PM +0100, Sebastian Mauer wrote:
Attached is a dump of the communication between BSC and nanoBTS when attempting to make a call.
Yeah, I was hoping to get some understanding of what's going wrong with the CRCX message. Before setting up the nanoBTS it was NVRAM reset so I am unsure if it's possible any old configuration would have been left over.
On Mon, 2 Aug 2021 at 00:01, Neels Hofmeyr nhofmeyr@sysmocom.de wrote:
Nothing interesting can be said about your IPACC_CRCX message. Compare a pcap of a normal assignment, taken from our test suite: https://jenkins.osmocom.org/jenkins/view/TTCN3/job/ttcn3-bsc-test/lastSucces...
Maybe someone else knows whether it can be a problem with the nanoBTS configuration? I can't help with those devices unfortunately.
~N