This makes no immediate reloads the default for runtornado, matching
the production configuration, and changes the development incantation
to be the one to specify the departure from the norm, with
--immediate-reloads.
Decouple the sending of client restart events from the restarting of
the servers. Restarts use the new Tornado restart-clients endpoint to
inject "restart" events into queues of clients which were loaded from
the previous Tornado process. The rate is controlled by the
`application_server.client_restart_rate`, in clients per minute, or a
flag to `restart-clients` which overrides it. Note that a web client
will also spread its restart over 5 minutes, so artificially-slow
client restarts are generally not very necessary.
Restarts of clients are deferred to until after post-deploy hooks are
run, such that the pre- and post- deploy hooks are around the actual
server restarts, even if pushing restart events to clients takes
significant time.
Note that this uses `ssh-keyscan` to write in the currently-observed
host fingerprint; if DNS or network is untrusted during initial puppet
apply, this can allow attackers to write their own host key, obviating
the utility of known_hosts.
We do not view this as a likely attack mechanism, since in our
deployment the network and DNS is almost certainly trusted, and if
not, the timing attack to catch only initial configuration is likely
impossible.
572443edc6 removed the callsite that triggered the exec in
`zulip::systemd_daemon_reload`, making its inclusion and ordering via
`require` moot.
Remove the call.
This should give some more room for systems that are still below 4GB
of RAM to use the lower-memory multithreaded mode, which is less
likely to have OOM kills (a very bad experience).
There should be little cost, as few systems are likely allocated with
memory in this range.
The only relevant changes are `PasswordAuthentication no` (which
is now the default) and `MaxStartups 40:50:60` (which is now
unneccesary due to autossh tunnels.
This was changed midway through the implementation, from reading it
from `zulip-secrets.conf`, and a couple locations still reference the
secrets path.