nut-server fails if modemmanager is scanning serial ports

[Lupe Christoph]

Similar to whatPaavo Leinonen reported in 031601ce2a49$20b2efe0$6218cfa0$@leinonen.fi on the NUT mailing list. See also my mail in reply.

Ubuntu runs modemmanager as a native upstart service. nut-server ends up running in parallel (on my system, probably a matter of timing). When modemmanager scans the serial ports for modems, upsd is unable to open the port configured for an UPS. (It might be possible to exclude some ports from the scan, I didn't check because I have no modem it could configure, I just kicked the package.

Please convert nut-server to a native upstart service to be able to have it wait for modemmanager. (I hope upstart is clever enough to have a service wait for an optional package and let it proceed if not installed.)

[Robie Basak (racb)]

Thank you for taking the time to report this bug and helping to make Ubuntu better.

IMHO, a more robust approach would be to make sure that modemmanager is using locks, and having upsd wait a small amount of time for the lock before giving up (possibly as a configurable option).

This mechanism would work across all packages that contend for the serial ports, rather than for us to have to deal with every single possible conflict individually.

[Launchpad Janitor (janitor)]

[Expired for modemmanager (Ubuntu) because there has been no activity for 60 days.]

[Launchpad Janitor (janitor)]

[Expired for nut (Ubuntu) because there has been no activity for 60 days.]