I run Red Hat Enterprise Linux release 8.5 (Ootpa) and have been running BOINC for years.
Today I had to reorganize my hard drives and moved the boinc stuff from one partition to another. That looked OK.
First, I stopped the boinc client, and that worked.
# systemctl stop boinc-client.service

Then I moved the files.
When I try to start the client, I do this

# systemctl start boinc-client

Dec 27 10:02:58 localhost systemd[1]: Started Berkeley Open Infrastructure Network Computing Client.
Dec 27 10:03:08 localhost boinc[465491]: 27-Dec-2021 10:03:08 Another instance of BOINC is running.
Dec 27 10:03:09 localhost systemd[1]: boinc-client.service: Main process exited, code=exited, status=108/n/a
Dec 27 10:03:09 localhost systemd[1]: boinc-client.service: Failed with result 'exit-code'.

I have no idea what to do next.

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P.S.:

ps -ef reveals nothing with .boinc in it except the grep ps -ef | grep boinc

jeandav+ 470157 469956 0 11:15 pts/0 00:00:00 grep --color=auto boinc

So there is no boinc client running.

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Whatta mess!

After a lot of spinning wheels, splitting hairs, and so on, I gave up and removed the boinc-client and boinc-manager and replaced them with the same thing I already had. I had the rpms on hand. Then I could get the boinc-client and boinc manager up, with no tasks in the machine (as I had left it) with no new tasks for anything. The system still got mad at me with errors every second or two.

This system runs with systemd and SELinux (security enhanced Linux) and it is very fussy. Even the super-user cannot do things. So I cleaned up a few rules and got it going. I then enabled new tasks for universe (because I do not care what happens to it) and it failed to download any, though it acquired a nice list trying to download. I then set the system to check and relabel all the files with SELinux (which involves a reboot), and that helped a lot more. So now I have it running. If it does all right with those, I may let another project run next. WCG, probably.

Then I have to remember how to tell systemd to start the boinc client on boot. But I have done that before, so I suspect I will be able to do it again. But a day wasted on a 15-minute job.

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