- This will leave /etc/{plinth,freedombox} empty by default making service more
robust to run across various environments and situations. See systemd's
explanation for more details.
- Use Debian maintainer scripts remove all the existing files in
/etc/plinth/modules-enabled.
- Read from /usr/share/freedombox/modules-enabled then from
/etc/plinth/modules-enabled and finally from /etc/freedombox/modules-enabled.
Later read ones override previously read files. Any file pointing to /dev/null
will mean the module must be ignored.
Tests:
- Clean up /etc/plinth, /etc/freedombox and
/usr/share/freedombox/modules-enabled. Run service and notice that files are
getting loaded from development folder using a debug message.
- Run setup.py and notice that files get installed in
/usr/share/freedombox/modules-enabled/ and in the next run they get loaded from
there.
- Create a override file in /etc/plinth/modules-enabled/transmission and notice
that overriden file gets priority over the one in
/usr/share/freedombox/modules-enabled.
- Link the file /etc/plinth/modules-enabled/transmission to /dev/null and notice
that is not loaded.
- Create another file in /etc/freedombox/modules-enabled/transmission and notice
that it overrides the previous two files.
- All affected modules are loaded.
- Build a new Debian package and ensure that upgrading 23.8 to new version
removes are all configuration files.
- Build developer documentation and test that Tutorial -> Full Code and Tutorial
-> Skeleton sections have been updated with references to
-.../modules-enabled/... paths.
- Install quassel and notice that certificates were copied to /var/lib/quassel
directory. Change domain to another domain and notice that certificates were
copied again to that directory.
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>
This is now the preferred location in Debian. See:
https://lintian.debian.org/tags/systemd-service-in-odd-locationhttps://bugs.debian.org/992465https://bugs.debian.org/987989d70caa69c6https://lists.debian.org/debian-devel/2021/08/msg00275.html
Tests:
- Lintian no longer shows errors:
E: freedombox: systemd-service-in-odd-location lib/.../calibre-server-freedombox.service
- Comparing the old .deb and newly generated .deb with these changes. All the
systemd files show that they are moved from /lib to /usr/lib/systemd.
- After upgrading the deb from older version to a version these changes,
services installed by the package are available (tested after restart with
wordpress and claibre). Services tweaked by the package have the changed
configuration reflected as shown by systemctl show
{service-name}.service (tested after restart with quassel).
Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>
Closes: Debian #805108.
Primary motivation is to provide swap for FreedomBox machines. On all FreedomBox
images, currently there is no swap configured. Swap on disk may not be good for
SBCs most of which use SD card for storage. We wish for processes to not get
killed when hard memory limit is reached.
Zram seems like a good solution to the problem suitable not only for SBCs but
also for desktops and bigger machines. Fedora is currently using Zram as its
default swap solution configured by the installer. Zram creates a block device
with a configured size. Writing blocks into the device compresses them and
stores them in RAM. This block device can be configured as swap among other
things. See:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/admin-guide/blockdev/zram.rst
Set the size of the swap to be 50% of RAM. Expected compression is about 1:2.
That means, in an average case, 25% of RAM is consumed to provide the swap
device. This results in the system being able to consume about 125% of RAM
capacity to run processes. This value is inspired by Fedora.
https://fedoraproject.org/wiki/Changes/SwapOnZRAM .
Zram based swap takes priority over disk based swap (due the priority being set
to 100). This reduces IO and improves latency on machines that already have a
swap device.
On containers, zramswap.service fails to start as it will not be possible to
insert the 'zram' kernel module from within the container. This should not cause
any further problems.
Since 'config' app is an essential app, zram-tools now becomes a hard dependency
of freedombox package.
For FreedomBox images, zram-tools will be pre-installed and pre-configured. So,
it will work on first boot. For users installing FreedomBox via apt or those
upgrading from an older version, zram-tools will be newly installed but
configuration will not be picked up until the next reboot. Restarting
zramswap.service is not done because it may not be a safe/successful operation.
systemd-zram-generator is a project that essentially does what zram-tools. It
appears to be a better implementation and we may migrate to it when it becomes
available in Debian. Migration expected to be straight forward.
Tests performed:
- Running `sudo -u plinth ./run --list-dependencies` shows zram-tools as a
dependency.
- On a container, `systemctl status zramswap.service` shows as failed.
- On a virtual machine, confirm that configuration is installed properly. Run
`./setup.py install; systemctl daemon-reload; systemctl show zramswap.service |
grep Environment`.
- On a virtual machine, ensure that you have more than 512MiB or RAM. Then
restart zramswap.service. This should create a swap space of 50% of RAM
capacity. Confirm with `free` and `zramswap status`.
- Restarting the VM retains the swap that has been setup.
Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>
Helps: #664.
Currently, logs are written to disk twice, once by journald and once by rsyslog.
rsyslog may log to multiple locations depending on the type of the log. To
reduce disk I/O, disable rsyslog and rely solely on systemd journal.
Place the code in config module as there is no better place for it currently
without creating a new module. Can be sorted later.
The following files under /var/log/ are no longer populated on FreedomBox. They
will be rotated away over a few days. Use journalctl instead to view the
messages:
- syslog
- messages*
- auth.log*
- debug*
- daemon.log
- kern.log
- lpr.log
- mail.log
- mail.info
- mail.warn
- mail.err
- user.log
Tests performed:
- On a machine with rsyslog running, run ./setup.py install and start FreedomBox
service. This triggers the config app's setup. rsyslog is disabled and masked.
systemd-journald is restarted.
- Even when rsyslog is unmaked and enabled manually, systemd journald does not
forward message to syslog anymore.
Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: Veiko Aasa <veiko17@disroot.org>
