hello list please the the entire mail thoroughly before answering. it's a neverending story with the bs-11 f***ing multidrop: i have bts0 that works perfect as single, and so does bts1, but only bts0 is bootstrapped lets start from the beginning: misdn is configured port 0 has ts1 as d-channel and 2-15 as b-channels, port 1 has ts17 as d-channel and 18-31 as b-channels. that says bs11_config for bts0, that is connected to pc: SITE MANAGER ATTRIBUTES: E1 Channel: Port=0 Timeslot=1 (Full Slot) TEI: 25 BS11 Line Interface ATTRIBUTES: PLL Mode: Standalone BS11 CCLK ATTRIBUTES: CCLK Accuracy: High (1) CCLK Type=0 BS11 Power Amplifier 0 ATTRIBUTES: TRX Power: 30mW (GSM) BPORT0 ATTRIBUTES: Line Configuration: Multi-Drop (1) BPORT1 ATTRIBUTES: Line Configuration: Multi-Drop (1) and that is bts1: SITE MANAGER ATTRIBUTES: E1 Channel: Port=1 Timeslot=17 (Full Slot) TEI: 26 BS11 Line Interface ATTRIBUTES: PLL Mode: Standalone BS11 CCLK ATTRIBUTES: CCLK Accuracy: High (1) CCLK Type=0 BS11 Power Amplifier 0 ATTRIBUTES: TRX Power: 30mW (GSM) BPORT0 ATTRIBUTES: Line Configuration: Star (0) BPORT1 GET ATTR NACK LMT LOGOFF: ACK as you can see, the d-channels match with the bts-setting. each bs-11 have a working trx0 and a high clock accuracy. here we go with cfg: ! ! OpenBSC configuration saved from vty ! ! password foo ! line vty no login ! network network country code 262 mobile network code 10 short name Y-Phone long name Yodaphone handover 1 bts 0 type bs11 band GSM900 cell_identity 1 location_area_code 1 training_sequence_code 7 base_station_id_code 63 oml e1 line 0 timeslot 1 sub-slot full oml e1 tei 25 trx 0 arfcn 121 max_power_red 0 rsl e1 line 0 timeslot 1 sub-slot full rsl e1 tei 1 timeslot 0 phys_chan_config CCCH+SDCCH4 e1 line 0 timeslot 1 sub-slot full timeslot 1 phys_chan_config TCH/F e1 line 0 timeslot 2 sub-slot 1 timeslot 2 phys_chan_config TCH/F e1 line 0 timeslot 2 sub-slot 2 timeslot 3 phys_chan_config TCH/F e1 line 0 timeslot 2 sub-slot 3 timeslot 4 phys_chan_config TCH/F e1 line 0 timeslot 3 sub-slot 0 timeslot 5 phys_chan_config TCH/F e1 line 0 timeslot 3 sub-slot 1 timeslot 6 phys_chan_config TCH/F e1 line 0 timeslot 3 sub-slot 2 timeslot 7 phys_chan_config TCH/F e1 line 0 timeslot 3 sub-slot 3 bts 1 type bs11 band GSM900 location_area_code 2 training_sequence_code 7 base_station_id_code 63 oml e1 line 1 timeslot 17 sub-slot full oml e1 tei 26 trx 0 arfcn 1 max_power_red 0 rsl e1 line 1 timeslot 17 sub-slot full rsl e1 tei 2 timeslot 0 phys_chan_config CCCH+SDCCH4 e1 line 1 timeslot 17 sub-slot full timeslot 1 phys_chan_config SDCCH8 e1 line 1 timeslot 18 sub-slot 1 timeslot 2 phys_chan_config TCH/F e1 line 1 timeslot 18 sub-slot 2 timeslot 3 phys_chan_config TCH/F e1 line 1 timeslot 18 sub-slot 3 timeslot 4 phys_chan_config TCH/F e1 line 1 timeslot 19 sub-slot 0 timeslot 5 phys_chan_config TCH/F e1 line 1 timeslot 19 sub-slot 1 timeslot 6 phys_chan_config TCH/F e1 line 1 timeslot 19 sub-slot 2 timeslot 7 phys_chan_config TCH/F e1 line 1 timeslot 19 sub-slot 3 both bs-11 works as single with the corresponding section (bts 0 or 1) of the cfg file. i have differents teis for all lapd connection. i use cat4 cable for the bs-11 connection (10 m between the bs-11s) maybe the screenshot attached unveils the problem. any help/hint is very welcome. T.