nginx service improvements

[arno01]

To address #5832

[lucabrunox]

Can we lower to 1sec? 10 sec is really too much in my opinion.

[arno01]

@lethalman it's not good as it will throw start request repeated too quickly for nginx.service

see as below, just tried:

[root@www:~/nixpkgs]# journalctl -b  |grep -v 'rejected connection' |tail -500 |egrep "emerg|nginx.service"
Jan 19 16:51:15 www nginx[22347]: nginx: [emerg] unknown directive "blablabla" in /nix/store/hash-nginx.conf:24
Jan 19 16:51:15 www systemd[1]: nginx.service: main process exited, code=exited, status=1/FAILURE
Jan 19 16:51:15 www systemd[1]: Unit nginx.service entered failed state.
Jan 19 16:51:15 www systemd[1]: nginx.service failed.
Jan 19 16:51:16 www systemd[1]: nginx.service holdoff time over, scheduling restart.
Jan 19 16:51:16 www nginx[22366]: nginx: [emerg] unknown directive "blablabla" in /nix/store/hash-nginx.conf:24
Jan 19 16:51:16 www systemd[1]: nginx.service: main process exited, code=exited, status=1/FAILURE
Jan 19 16:51:16 www systemd[1]: Unit nginx.service entered failed state.
Jan 19 16:51:16 www systemd[1]: nginx.service failed.
Jan 19 16:51:17 www systemd[1]: nginx.service holdoff time over, scheduling restart.
Jan 19 16:51:17 www nginx[22376]: nginx: [emerg] unknown directive "blablabla" in /nix/store/hash-nginx.conf:24
Jan 19 16:51:17 www systemd[1]: nginx.service: main process exited, code=exited, status=1/FAILURE
Jan 19 16:51:17 www systemd[1]: Unit nginx.service entered failed state.
Jan 19 16:51:17 www systemd[1]: nginx.service failed.
Jan 19 16:51:19 www systemd[1]: nginx.service holdoff time over, scheduling restart.
Jan 19 16:51:19 www nginx[22384]: nginx: [emerg] unknown directive "blablabla" in /nix/store/hash-nginx.conf:24
Jan 19 16:51:19 www systemd[1]: nginx.service: main process exited, code=exited, status=1/FAILURE
Jan 19 16:51:19 www systemd[1]: Unit nginx.service entered failed state.
Jan 19 16:51:19 www systemd[1]: nginx.service failed.
Jan 19 16:51:20 www systemd[1]: nginx.service holdoff time over, scheduling restart.
Jan 19 16:51:20 www nginx[22392]: nginx: [emerg] unknown directive "blablabla" in /nix/store/hash-nginx.conf:24
Jan 19 16:51:20 www systemd[1]: nginx.service: main process exited, code=exited, status=1/FAILURE
Jan 19 16:51:20 www systemd[1]: Unit nginx.service entered failed state.
Jan 19 16:51:20 www systemd[1]: nginx.service failed.
Jan 19 16:51:21 www systemd[1]: nginx.service holdoff time over, scheduling restart.
Jan 19 16:51:21 www systemd[1]: start request repeated too quickly for nginx.service
Jan 19 16:51:21 www systemd[1]: Unit nginx.service entered failed state.
Jan 19 16:51:21 www systemd[1]: nginx.service failed.

5 times tried to restart and gave up with start request repeated too quickly for nginx.service

[arno01]

Might be a good idea to add Use StartLimitBurst= to configure how many starts per interval are allowed
not sure what's the default value of it.

or keep it to at least 5s ..
actually the same should be done in the dovecot commit #5845 where you changed it to 1s

[lucabrunox]

@arno01 we can think of it. It's certainly an improvement over the previous Restart=no default. It's so dependent on the target the system, that after all you can change those values. It's not that we can decide a good value for every system, as this is mainly an hack for a more graceful failure by default.

I have no strong opinion on this, except that 10s is too much.

[arno01]

This delay 5s doesn't generate any friction, but only ensures that the service is started.
If it was anyway started from the first time, then it wasn't delayed at all as it is RestartSec parameter on-failure only.
So when something is wrong, it will give it 5s or 10s before retrying.. and this something is wrong might really need 5s as we know the dhcpd problem now #5832 (comment) ...

with 1s it will try just 4-5 times (takes only 5 seconds before systemd gaves up) which is not enough

[arno01]

@lethalman okay then, 5s should be enough

[lucabrunox]

Merging this, I think it's a good to have default.