Hello all,
I'm attempting to connect multiple BTS's to one E1 card. Each BTS is a
single TRX and I'm using a dahdi card plugged into a DCS. The DCS maps the
channels as follows:
Name Src Dest Speed
Type
--------------------------------------------------------------------------------
bscnok1 01.T1E1-A.02.01 01.T1E1-A.03.01 0256k D
FDX
bscnok2 01.T1E1-A.02.05 01.T1E1-A.04.01 0256k D
FDX
bscnok3 01.T1E1-A.01.09 01.T1E1-B.01.01 0256k D
FDX
So essentially:
TS 1,2,3,4 from OpenBSC (T1E1-A-02) are mapped to nok1 1,2,3,4 (T1E1-A-03)
TS 5,6,7,8 from OpenBSC (T1E1-A-02) are mapped to nok2 1,2,3,4 (T1E1-A-04)
TS 9,10,11,12 from OpenBSC (T1E1-A-02) are mapped to nok3 1,2,3,4
(T1E1-B-01)
This all works fine. The BTS operates on TS1,2,3,4 on any of the ports I
have configured. I just swap timeslots in openbsc.cfg from 1,2,3,4 to
5,6,7,8 or 9,10,11,12 and everything is happy.
Where I run into a problem is when I try to actually run multiple BTS's at
once. So I take everything defined in "bts 0" and duplicate it as "bts
1".
I change the time slots for oml, rsl, and traffic channels to match the
appropriate channels for bts 1/2. But when I go to start osmo-nitb I get an
error that it can't open /dev/dahdi/1 because it's already in use. It
appears for some reason that it's attempting to open /dev/dahdi/1 for both
BTS's even though only bts 0 uses /dev/dahdi/1 for OML - bts 1 should use
/dev/dahdi/5 and bts 2 should use /dev/dahdi/9.
My /etc/dahdi/system.conf is defined as:
span=1,1,0,ccs,hdb3,crc4
bchan=2-4,6-8,10-12
dchan=1,5,9
I'm at a loss. Has anyone tried to run multiple BTS's with dahdi on a
single E1 or T1 span? Is there something special I need to specify so that
OpenBSC doesn't grab the first dchan for each BTS?
Thanks,
Gus