OsmocomBB

not sure which nutjob is maintaining ubuntu nowadays, but i had to remove some packages from this 'supposed server' image to make it not shitty and breaking for us:
purge snap, unattended-upgrades, cloud*, netplan.io, ubuntu-advantage-tools, open-vm-tools and everything which depends on em.

then one can use 'normal' network config again, and not some may-work-sometimes-when-the-mac-is-even-and-its-thursday crud.
i went for /etc/systemd/network/10-eth0.network

no clue why it still uses eth0.

please lets use maintainable and not broken-by-default images as base in the future.

ssh password auth is disabled (not default on ubuntu!)
keys for hoernchen,laforge,osmith are installed for user ubuntu (has sudo)

the apu was no issue. user is root, keys like above.

the plan is to put it in the top end of the testrack on ports 19 and 20 of the upper switch (testrack1)
for now i have placed it in the lab on a desk for ease of debugging.

• 10.9.25.150 mssdr-bts (apu)
• 10.9.25.151 mssdr-ms (rpi4)

i have put a 6V psu on the usrp, but i'm not sure it needs it. for me they were flaykey sometimes when only powered by usb. no clue what bladerf needs or does, since it seems to depend on the order of powerup of devices?! please advice what worked for you.

clock is just a simple splitter, when its in the other rack its the proper 10mhz distribution amp.

please log in and give it a try.

for rf its only simple flex and 30db attentuators between RX1 and TX1 of both devices. if you'd like a rfdsatt here, give me a shout.

After some investigation and remote debugging for Hoernchen, I discovered that roh had labelled the Rx/Tx of the USRP wrong. The label for Port A/1 were (and still is) swapped. So you ended up connecting Tx to Tx and Rx to Rx.

• swap the RG178 cables with rigid-flex RG402
• remove the 30dB attenuators
• measure the signal levels with an RfExplorer
  • the RfExplorer showed the carriers something like 400-500 kHz above the expected frequency. Is it off that much?

I re-introduced the 30dB attenuators and kept the rigid-flex connections.

roh, please make sure to swap the label to propely indicate Rx/Tx. Next time I would hope something trivial like that doesn't need my intervention...

The setup finally appears to work as expected, after stumbling into https://osmocom.org/issues/4832 due to my copied stp config not working for some reason until I just dumped the actual running config instead of relying upon the dynamic auto setup, there was "no" msc available, and this led to opening and then immediately closing the dl channel during LU attempts, which caused tons of bit errors and obviously looked like additional rf issues in the DL..

roh feel free to move the test setup to a more permanent location - just mention it here first, so I don't end up wondering if it crashed..

setup is moved to the rack.

i think both sdr are happy, but please give it a thorough checkover - had to swap some cables over due to length constraints.

it now lives on the right side of the BGT frame, the apu is a bit lower in the rack, there was simply no other space.

the labels are fixed. it seems i assumed the same layout for both channels when printing those, not a 'mechanical mirrored one' - my bad.