The previous model for these Nagios checks was kinda crazy -- every
minute, we'd run a full `rabbitmctl list_consumers` for each of the
dozen+ consumers that we have, and then do the exact same parsing
logic for each to determine whether the target queue has a running
consumer to write out a state file.
Because `rabbitmctl list_consumers` takes a small amount of resources,
on systems where CPU is very limited (e.g. t2 style AWS instances),
this minor CPU wastage could be problematic.
Now we just do that `rabbitmqctl list_consumers` once per minute, and
output all the state files from a single command.
Further TODO items on this front include removing the hardcoded list
of queues.
Because rabbitmq doesn't support changing the nodename of a running
rabbitmq node, Zulip installations suffered a plague of issues where
e.g. a Zulip server would reboot, the hostname would change, and
suddenly the local rabbitmq instance being used by Zulip would stop
working.
We address this problem by using, by default, a fixed rabbitmq
nodename, but providing server administrators the option to set the
rabbitmq nodename used by Zulip however they choose.
To upgrade an existing server to use this new configuration, one will
need to add something like the following to /etc/zulip/zulip.conf:
[rabbitmq]
nodename = zulip@localhost
However, I don't believe we have the puppet code in place to make this
work correctly at initial installation without rabbitmq-server being
already installed (but off), as we can easily setup in Travis CI but I
haven't been willing to do for the installer. So for now, this just
fixes our Travis CI problems.
Fixes: #1579.
Travis CI seems to have changed the way the snakeoil SSL certs are
generated in their infrastructure, so we need to update our expected
"success" HTTP headers accordingly.
Run '/puppet/zulip/files/nagios_plugins/zulip_app_frontend/check_send_receive_time'
script as 'zulip' user so that the connection to the database can be
made correctly.
Previously, we were wasting time every time we installed packages,
because `apt-get upgrade` would only install most of the packages
`apt-get dist-upgrade` would.
Camo is a caching image proxy, used in Zulip to avoid mixed-content
warnings by proxying HTTP image content over HTTPS. We've been using
it in zulip.com production for years; this change makes it available
in standalone Zulip deployments.
This should save several minutes off the Travis CI `production`
suite's runtime, since previously we were doing the full apt upgrade
process twice, resulting in things like multiple expensive rebuilds of
the initramfs.
Travis CI's model of installing every version of postgres on the test
VM and then shutting all the versions other than the one requested
down seems to not work very well with doing apt upgrades. It seems
the best way to resolve this is to just uninstall the versions we
don't need.
We ran into a bug with the Travis CI infrastructure where it postgres
9.1 is installed on the system, and so when we'd do an apt upgrade
with a new version of 9.1, the 9.1 daemon would end up getting started
and conflict with the 9.3 daemon we were trying to run.
With this change, we are now testing the production static asset
pipeline and installation process in a new testing job (and also run
the frontend/backend tests separately).
This means that changes that break the Zulip static asset pipeline or
production installation process are more likely to fail tests. The
testing is imperfect in that it does not have proper isolation -- we
build a complete Zulip development environment and then install a
Zulip production environment on top of it, so e.g. any apt
dependencies installed for Zulip development will still be available
for the Zulip production environment. But, it's better than nothing!
A good v2 of this would be to have the production setup process just
install the minimum stuff needed to run `build-release-tarball` and
then uninstall it / clean it up so that we can do a more clear
production installation, but that's more work.
Vishnu Ks
Tim Abbott
Umair Khan