syncoid: systemd.unit + debian

[crpb]

Hi,

as i was writing a systemd.service/time because in the 'Issues' people only said they created them but didn't share anything about it and so i began to try out a couple few things how this could be realized in a good way.

Well, it isn't finished, or rather not what it could be, but at least it works for a simple one-to-one synchronization for now.

And in that process as i'm using Debian and wanted to build/install to check if that works as expected i also did a bit of work in the debian-folder. Tho i haven't upgraded the Packaing-Version or format. But at least i could remove all those directives in the debian/rules

I think log's say more than a thousand words 🙈

% dpkg-deb --contents ../sanoid_2.2.1_all.deb
drwxr-xr-x root/root         0 2023-02-10 22:15 ./
drwxr-xr-x root/root         0 2023-02-10 22:15 ./lib/
drwxr-xr-x root/root         0 2023-02-10 22:15 ./lib/systemd/
drwxr-xr-x root/root         0 2023-02-10 22:15 ./lib/systemd/system/
-rw-r--r-- root/root       312 2023-02-10 22:15 ./lib/systemd/system/sanoid-prune.service
-rw-r--r-- root/root       272 2023-02-10 22:15 ./lib/systemd/system/sanoid.service
-rw-r--r-- root/root       124 2023-02-10 22:15 ./lib/systemd/system/sanoid.timer
-rw-r--r-- root/root       387 2023-02-10 22:15 ./lib/systemd/system/syncoid.service
drwxr-xr-x root/root         0 2023-02-10 22:15 ./usr/
drwxr-xr-x root/root         0 2023-02-10 22:15 ./usr/sbin/
-rwxr-xr-x root/root      3988 2023-02-10 22:15 ./usr/sbin/findoid
-rwxr-xr-x root/root     59062 2023-02-10 22:15 ./usr/sbin/sanoid
-rwxr-xr-x root/root     79605 2023-02-10 22:15 ./usr/sbin/syncoid
drwxr-xr-x root/root         0 2023-02-10 22:15 ./usr/share/
drwxr-xr-x root/root         0 2023-02-10 22:15 ./usr/share/doc/
drwxr-xr-x root/root         0 2023-02-10 22:15 ./usr/share/doc/sanoid/
-rw-r--r-- root/root        92 2023-02-10 22:15 ./usr/share/doc/sanoid/README.Debian
-rw-r--r-- root/root      6842 2023-02-10 22:15 ./usr/share/doc/sanoid/README.md.gz
-rw-r--r-- root/root       632 2023-02-10 22:15 ./usr/share/doc/sanoid/TODO
drwxr-xr-x root/root         0 2023-02-10 22:15 ./usr/share/doc/sanoid/changelog/
-rw-r--r-- root/root      6721 2023-02-10 22:15 ./usr/share/doc/sanoid/changelog/CHANGELIST.gz
-rw-r--r-- root/root      2114 2023-02-10 22:15 ./usr/share/doc/sanoid/changelog/dh_installchangelogs.dch.trimmed.gz
-rw-r--r-- root/root      1134 2023-02-10 22:15 ./usr/share/doc/sanoid/copyright
drwxr-xr-x root/root         0 2023-02-10 22:15 ./usr/share/doc/sanoid/examples/
-rw-r--r-- root/root      3945 2023-02-10 22:15 ./usr/share/doc/sanoid/examples/sanoid.conf
-rw-r--r-- root/root      1266 2023-02-10 22:15 ./usr/share/doc/sanoid/examples/syncoid.conf
-rw-r--r-- root/root       267 2023-02-10 22:15 ./usr/share/doc/sanoid/examples/syncoid.timer
drwxr-xr-x root/root         0 2023-02-10 22:15 ./usr/share/man/
drwxr-xr-x root/root         0 2023-02-10 22:15 ./usr/share/man/man8/
-rw-r--r-- root/root       498 2023-02-10 22:15 ./usr/share/man/man8/findoid.8.gz
-rw-r--r-- root/root       863 2023-02-10 22:15 ./usr/share/man/man8/sanoid.8.gz
-rw-r--r-- root/root      2322 2023-02-10 22:15 ./usr/share/man/man8/syncoid.8.gz
drwxr-xr-x root/root         0 2023-02-10 22:15 ./usr/share/sanoid/
-rw-r--r-- root/root      4685 2023-02-10 22:15 ./usr/share/sanoid/sanoid.defaults.conf

The manpages were created with. Maybe this could be done with a Makefile instead?

help2man -N -s 8 -o findoid.8 /usr/sbin/findoid
help2man -N -s 8 -o syncoid.8 /usr/sbin/syncoid
help2man -N -s 8 -o sanoid.8 /usr/sbin/sanoid

syncoid.service will only work with a existant /etc/sanoid/syncoid.conf but will not spew out any errors if it isn't configured.

syncoid.conf has a bunch of comments on how and why i did it like that.
i wondered while i was trying out some things if it wouldn't be better to have syncoid parse an actual configfile like sanoid does which will also allow non-systemd users to make use of it? 🙊

PS: i suppose this can PR can be worked on a while as i'm not totaly happy with it but maybe someone else has a good idea and thats why i stopped here for now 🙉

Cheers

[jimsalterjrs]

@phreaker0 are you a systemd person? I don't ever use systemd timers, so I don't feel entirely comfortable dogfooding this one. But if we can get a couple independent confirmations that it's good, seems like it would be a nice thing to go ahead and merge.

[bjodah]

So I'm just getting started using sanoid, and saw this PR so I thought I should give it a go.
After building the .deb and installing it using apt, I was somewhat surprised that the folder /etc/sanoid wasn't created. Fair enough, I created it and crafted a sanoid.conf for my taste. I tried running sanoid:

# TZ=UTC sanoid --take-snapshots --verbose
FATAL: cannot load /etc/sanoid/sanoid.defaults.conf - please restore a clean copy, this is not a user-editable file! at /usr/sbin/sanoid line 880.

I can see that this PR installs the sanoid.defaults.conf file under /usr/share/sanoid/ instead, am I supposed to move copy this file to /etc/sanoid/?

Doing allows the command to finish successfully.

Moving on to configure syncoid I look for a syncoid.conf file, but I cannot find one in neither /etc/sanoid nor /usr/share/{sanoid,syncoid}. Looking at the diff in this PR I think it looks like the example config is not really copied by the install script?

And finally, I wanted to enable the systemd services. I'm not terribly familiar with systemd yet, but shouldn't one be expected to find the services listed by this command?

# systemctl list-units --all | grep -E '(sanoid|syncoid)'
#

Forgive any misconceptions on my part, I'm not terribly proficient with systemd, to say the least. Thank you for working on this!

EDIT: also, the --include-datasets= option referred to in syncoid.conf looks... undocumented?

[phreaker0]

@bjodah this PR removes the install of /etc/sanoid, I don't know why and it obviously breaks stuff. You can use the latest master/release version to build your deb.

@crpb IMHO there shouldn't be a shipped system service/timer for syncoid, as replication will in most cases be more specific which can't be covered by a single src/target setup. I for example have serveral replication timers/services for may different pools and hosts. Furthermore replication shouldn't be tied to sanoid-prune by default.
But a documented example for a systemd service/timer would be nice.

[crpb]

@phreaker0

this PR removes the install of /etc/sanoid, I don't know why

thats because i took a few parts from the package in debian. the config isn't shipped by default and is only mentioned in the README.Debian. and i didn't realize that removing it from rules will do that 🙃

• mark /etc/sanoid/sanoid.conf as conffile again

there shouldn't be a shipped system service/timer for syncoid, as replication will in most cases be more specific

yeah, it was a first trial. also see those remarks which would probably end in a much more complex thing.
i don't realy have enough case examples i could come up with as i only use it for my workstation, laptop and one rootserver. the other zfs-driven systems i have are truenas which obviously don't have any need for sanoid 👀

• syncoid.service -> examples

Furthermore replication shouldn't be tied to sanoid-prune

with my first tests i had a timer like in the example running but wasn't 100% if that could messy if both sanoid and syncoid start on the same time so i later hooked it to sanoid-prune which, for my simple replicationscheme, works so far.

• untie syncoid.service