These checks suffer from a couple notable problems:
- They are only enabled on staging hosts -- where they should never
be run. Since ef6d0ec5ca, these supervisor processes are only
run on one host, and never on the staging host.
- They run as the `nagios` user, which does not have appropriate
permissions, and thus the checks always fail. Specifically,
`nagios` does not have permissions to run `supervisorctl`, since
the socket is owned by the `zulip` user, and mode 0700; and the
`nagios` user does not have permission to access Zulip secrets to
run `./manage.py print_email_delivery_backlog`.
Rather than rewrite these checks to run on a cron as zulip, and check
those file contents as the nagios user, drop these checks -- they can
be rewritten at a later point, or replaced with Prometheus alerting,
and currently serve only to cause always-failing Nagios checks, which
normalizes alert failures.
Leave the files installed if they currently exist, rather than
cluttering puppet with `ensure => absent`; they do no harm if they are
left installed.
These thresholds are in relationship to the
`autovacuum_freeze_max_age`, *not* the XID wraparound, which happens
at 2^31-1. As such, it is *perfectly normal* that they hit 100%, and
then autovacuum kicks in and brings it back down. The unusual
condition is that PostgreSQL pushes past the point where an autovacuum
would be triggered -- therein lies the XID wraparound danger.
With the `autovacuum_freeze_max_age` set to 2000000000 in
`postgresql.conf`, XID wraparound happens at 107.3%. Set the warning
and error thresholds to below this, but above 100% so this does not
trigger constantly.
This verifies that the proxy is working by accessing a
highly-available website through it. Since failure of this equates to
failures of Sentry notifications and Android mobile push
notifications, this is a paging service.
Since this was using repead individual get() calls previously, it
could not be monitored for having a consumer. Add it in, by marking
it of queue type "consumer" (the default), and adding Nagios lines for
it.
Also adjust missedmessage_emails to be monitored; it stopped using
LoopQueueProcessingWorker in 5cec566cb9, but was never added back
into the set of monitored consumers.
7d4a370a57 attempted to move the replication check to on the
PostgreSQL hosts. While it updated the _check_ to assume it was
running and talking to a local PostgreSQL instance, the configuration
and installation for the check were not updated. As such, the check
ran on the nagios host for each DB host, and produced no output.
Start distributing the check to all apopdb hosts, and configure nagios
to use the SSH tunnel to get there.
wal-g was used in `puppet/zulip` by env-wal-g, but only installed in
`puppet/zulip_ops`.
Merge all of the dependencies of doing backups using wal-g (wal-g
installation, the pg_backup_and_purge job, the nagios plugin that
verifies it happens) into a common base class in `puppet/zulip`, since
it is generally useful.
check_memcached does not support memcached authentication even in its
latest release (it’s in a TODO item comment, and that’s it), and was
never particularly useful.
In Bionic, nagios-plugins-basic is a transitional package which
depends on monitoring-plugins-basic. In Focal, it is a virtual
package, which means that every time puppet runs, it tries to
re-install the nagios-plugins-basic package.
Switch all instances to referring to `$zulip::common::nagios_plugins`,
and repoint that to monitoring-plugins-basic.
65774e1c4f switched from using the bundled check_postgres.pl to using
the version from packages; the file itself remained, however.
Remove it, and clean up references to it.
Fixes#15389.
Instead of SSH'ing around to them, run directly on the database hosts.
This means that the replicas do not know how many bytes behind they
are in _receiving_ the wall logs; thus, the monitoring also extends to
the primary database, which knows that information for each replica.
This also allows for detecting when there are too few active replicas.
This no longer has any rules specific to it. We leave the `postgres`
munin group (which now only contains `postgres_appdb`) as
future-proofing, and so that `postgres_appdb` matches to the puppet
manifest of the same name.
While this functionality to post slow queries to a Zulip stream was
very useful in the early days of Zulip, when there were only a few
hundred accounts, it's long since been useless since (1) the total
request volume on larger Zulip servers run by Zulip developers, and
(2) other server operators don't want real-time notifications of slow
backend queries. The right structure for this is just a log file.
We get rid of the queue and replace it with a "zulip.slow_queries"
logger, which will still log to /var/log/zulip/slow_queries.log for
ease of access to this information and propagate to the other logging
handlers. Reducing the amount of queues is good for lowering zulip's
memory footprint and restart performance, since we run at least one
dedicated queue worker process for each one in most configurations.
"Zulip Voyager" was a name invented during the Hack Week to open
source Zulip for what a single-system Zulip server might be called, as
a Star Trek pun on the code it was based on, "Zulip Enterprise".
At the time, we just needed a name quickly, but it was never a good
name, just a placeholder. This removes that placeholder name from
much of the codebase. A bit more work will be required to transition
the `zulip::voyager` Puppet class, as that has some migration work
involved.
This legacy cross-realm bot hasn't been used in several years, as far
as I know. If we wanted to re-introduce it, I'd want to implement it
as an embedded bot using those common APIs, rather than the totally
custom hacky code used for it that involves unnecessary queue workers
and similar details.
Fixes#13533.
Zulip has had a small use of WebSockets (specifically, for the code
path of sending messages, via the webapp only) since ~2013. We
originally added this use of WebSockets in the hope that the latency
benefits of doing so would allow us to avoid implementing a markdown
local echo; they were not. Further, HTTP/2 may have eliminated the
latency difference we hoped to exploit by using WebSockets in any
case.
While we’d originally imagined using WebSockets for other endpoints,
there was never a good justification for moving more components to the
WebSockets system.
This WebSockets code path had a lot of downsides/complexity,
including:
* The messy hack involving constructing an emulated request object to
hook into doing Django requests.
* The `message_senders` queue processor system, which increases RAM
needs and must be provisioned independently from the rest of the
server).
* A duplicate check_send_receive_time Nagios test specific to
WebSockets.
* The requirement for users to have their firewalls/NATs allow
WebSocket connections, and a setting to disable them for networks
where WebSockets don’t work.
* Dependencies on the SockJS family of libraries, which has at times
been poorly maintained, and periodically throws random JavaScript
exceptions in our production environments without a deep enough
traceback to effectively investigate.
* A total of about 1600 lines of our code related to the feature.
* Increased load on the Tornado system, especially around a Zulip
server restart, and especially for large installations like
zulipchat.com, resulting in extra delay before messages can be sent
again.
As detailed in
https://github.com/zulip/zulip/pull/12862#issuecomment-536152397, it
appears that removing WebSockets moderately increases the time it
takes for the `send_message` API query to return from the server, but
does not significantly change the time between when a message is sent
and when it is received by clients. We don’t understand the reason
for that change (suggesting the possibility of a measurement error),
and even if it is a real change, we consider that potential small
latency regression to be acceptable.
If we later want WebSockets, we’ll likely want to just use Django
Channels.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
This has been a spurious alert for a long time.
It's unclear that this check is useful at all, but if it spikes
dramatically above what's normal, there's perhaps still utility in
being alerted.
Since LoopQueueProcessingWorker jobs cannot be monitored by checking
for connected consumers (since they poll, rather than consuming as
events arrive), they can't be monitored with check_consumers. It's
OK, because that monitoring was redundant with monitoring for
potential growth in their queue that we have as well.
Also clean up the block comments for the two other similar queue
procesors.
Delete trailing newlines from all files, except
tools/ci/success-http-headers.txt and tools/setup/dev-motd, where they
are significant, and static/third, where we want to stay close to
upstream.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
Running this on additional machines would be redundant; additionally,
the FillState checker cron job runs only on cron systems, so this will
crash on other app frontends.
Revert c8f034e9a "queue: Remove missedmessage_email_senders code."
As the comment in the code says, it ensures a smooth upgrade path
from 1.7.x; we can delete it in master after 1.8.0 is released.
The removal commit was merged early due to a communication failure.
This commit just copies all the code from MissedMessageSendingWorker
class to a new EmailSendingWorker class. All the logic to send an email
through a queue was already there. This commit only makes the logic
generic. It does so by creating a special purpose queue called
'email_senders' to send any type of email. To make
MissedMessageSendingWorker still work we derive it from
EmailSendingWorker. All the tests that were testing
MissedMessageSendingWorker now run against EmailSendingWorker.
This fixes a bug where, when a user is unsubscribed from a stream,
they might have unread messages on that stream leak. While it might
seem to be a minor problem, it can cause significant problems for
computing the `unread_msgs` data structures, since it means we need to
add an extra filter for whether the user is still subscribed, either
in the backend or in the UI.
Fixes#7095.
Alex Vandiver
Anders Kaseorg
Tim Abbott
Alex Vandiver
Mateusz Mandera
Tim Abbott
Stefan Weil
Anders Kaseorg
Greg Price
Umair Khan
Rishi Gupta
Vishnu Ks
Tim Abbott