Upgrading ubuntu breaks zoneminder

[lennyg]

I upgraded from Ubuntu 18.04 to 20.04, but didn't upgrade ZoneMinder, which is on 1.34.26. ZM won't come up. I'm getting
Can't open memory map file /dev/shm/zm.mmap.1, probably not enough space free: No such file or directory

/dev/shm is on tmpfs, which has 3041780K available. I read somewhere about changing /proc/sys/kernel/shmmax. When I cat /proc/sys/kernel/shmmax, get 18446744073692774399.

Any suggestions on what I should be doing? Should I upgrade to 1.36?

Thanks

[rebornjumpman]

Glad to see I'm not the only one with this problem. This morning I ran updates on my Debian 10 server which upgraded ZM from 1.34.25 to 1.34.26 and now monitors show a broken image icon with no picture. I've had this happen before and the only way I was able to fix it was to start all over from scratch, so I've been intentional about not updating ZM from 1.34.25 until today when I ran it by accident. I'm hoping to avoid all of that extra work if possible. so if anyone here knows how to get ZM working again I'm up for trying anything!

[Magic919]

Best to hold the package if you don't plan to upgrade the version.

Logs might give some clues.

[iconnor]

Maybe you just need to run zmupdate.pl

Debian is known for not doing these things automatically.