These are just defensive cleanup tasks that we run.
In the good case, there's nothing to kill or remove, so they trigger an
error like this:
> Error response from daemon: Cannot kill container: something: No such container: something
and:
> Error: No such container: something
People often ask us if this is a problem, so instead of always having to
answer with "no, this is to be expected", we'd rather eliminate it now
and make logs cleaner.
In the event that:
- a container is really stuck and needs cleanup using kill/rm
- and cleanup fails, and we fail to report it because of error
suppression (`2>/dev/null`)
.. we'd still get an error when launching ("container name already in use .."),
so it shouldn't be too hard to investigate.
Not specifying bind addresses for the worker resulted in this warning:
> synapse.app - 47 - WARNING - None - Failed to listen on 0.0.0.0, continuing because listening on [::]
Additionally, metrics listening only on 127.0.0.1 seems like a no-op.
Only having it accessible from within the container is likely not what
we intend. Changed that to all interfaces as well.
Whether it actually gets exposed or not depends on the systemd service
and `matrix_synapse_workers_container_host_bind_address`.
This switches the `docker exec` method of spawning
Synapse workers inside the `matrix-synapse` container with
dedicated containers for each worker.
We also have dedicated systemd services for each worker,
so this are now:
- more consistent with everything else (we don't use systemd
instantiated services anywhere)
- we don't need the "parse systemd instance name into worker name +
port" part
- we don't need to keep track of PIDs manually
- we don't need jq (less depenendencies)
- workers dying would be restarted by systemd correctly, like any other
service
- `docker ps` shows each worker separately and we can observe resource
usage
There was a `matrix_nginx_proxy_enabled|default(False)` check, but:
- it didn't seem to work reliably for some reason (hmm)
- referring to a `matrix_nginx_proxy_*` variable from within the
`matrix-synapse` role is not ideal
- exposing always happened on `127.0.0.1`, which may not be good enough
for some rarer setups (where the own webserver is external to the host)
The Docker 19.04 -> 20.10 upgrade contains the following change
in `/usr/lib/systemd/system/docker.service`:
```
-BindsTo=containerd.service
-After=network-online.target firewalld.service containerd.service
+After=network-online.target firewalld.service containerd.service multi-user.target
-Requires=docker.socket
+Requires=docker.socket containerd.service
Wants=network-online.target
```
The `multi-user.target` requirement in `After` seems to be in conflict
with our `WantedBy=multi-user.target` and `After=docker.service` /
`Requires=docker.service` definitions, causing the following error on
startup for all of our systemd services:
> Job matrix-synapse.service/start deleted to break ordering cycle starting with multi-user.target/start
A workaround which appears to work is to add `DefaultDependencies=no`
to all of our services.
ma1sd requires the openid endpoints for certain functionality.
Example: 90b2b5301c/src/main/java/io/kamax/mxisd/auth/AccountManager.java (L67-L99)
If federation is disabled, we still need to expose these openid APIs on the
federation port.
Previously, we were doing similar magic for Dimension.
As per its documentation, when running unfederated, one is to enable
the openid listener as well. As per their recommendation, people
are advised to do enable it on the Client-Server API port
and use the `federationUrl` variable to override where the federation
port is (making federation requests go to the Client-Server API).
Because ma1sd always uses the federation port (unless you do some
DNS overwriting magic using its configuration -- which we'd rather not
do), it's better if we just default to putting the `openid` listener
where it belongs - on the federation port.
With this commit, we retain the "automatically enable openid APIs" thing
we've been doing for Dimension, but move it to the federation port instead.
We also now do the same thing when ma1sd is enabled.
`-v` magically creates the source destination as a directory,
if it doesn't exist already. We'd like to avoid this magic
and the potential breakage that it might cause.
We'd rather fail while Docker tries to find things to `--mount`
than have it automatically create directories and fail anyway,
while having contaminated the filesystem.
There's a lot more `-v` instances remaining to be fixed later on.
This is just some start.
Things like `matrix_synapse_container_additional_volumes` and
`matrix_nginx_proxy_container_additional_volumes` were not changed to
use `--mount`, as options for each one are passed differently
(`ro` is `ro`, but `rw` doesn't exist and `slave` is `bind-propagation=slave`).
To avoid breaking people's custom volume mounts, we keep it as it is for now.
A deficiency with `--mount` is that it lacks the `z` option (SELinux
ownership changes), and some of our `-v` instances use that. I'm not
sure how supported SELinux is for us right now, but it might be,
and breaking that would not be a good idea.
also, worker.yaml.j2:
- hone worker_name
- remove worker_pid_file entry (would only be used if worker_daemonize
set to true; also, synapse only knows about the container namespace
and thus can not provide the required host-view PID)
- cherry-pick "Ensure worker config exists in systemd service (#7528)"
from synapse d74cdc1a42e8b487d74c214b1d0ca575429d546a:
"check that the worker config file exists instead of silently failing."
Depending on the distro, common commands like sleep and chown may either
be located in /bin or /usr/bin.
Systemd added path lookup to ExecStart in v239, allowing only the
command name to be put in unit files and not the full path as
historically required. At least Ubuntu 18.04 LTS is however still on
v237 so we should maintain portability for a while longer.
