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.
This reverts commit 3f95e567c1.
Apparently `apt-add-repository` fails periodically in CI. I suspect
this is some sort of silly networking problem, but given that all
we're saving is a few lines of code, the old version was better if
this fails basically ever.
Previously, the install script would fail if you passed various
non-default puppet rules, since the code to configure and restart
services that runs later on in the install script largely ran
unconditionally, regardless of whether the relevant service was
actually installed on the target system.
This should make the main install script reusable for installing
e.g. a dedicated Postgres server for use with Zulip.
This reverts commit f1f48f305e.
The use of sklearn unfortunately caused a substantial slowdown to the
Zulip provisioning process, which didn't seem worth it for a
relatively minor feature.
Apparently, puppet has messed up exit codes and doesn't by default
return the usual 0=success, nonzero=failure codes. By default, it
seems to always return 0; and with `--detailed-exitcodes`, it returns
the complicated thing documented in the comments.
We fix this by checking the exit code and translating it to what we
actually care about, namely whether errors occurred.
See https://tickets.puppetlabs.com/browse/PUP-2754 for details.
Fixes#1094.
In python 3, subprocess uses bytes for input and output if
universal_newlines=False (the default). It uses str for input and
output if universal_newlines=True.
Since we're dealing with strings here, add universal_newlines=True
to subprocess.check_output calls.
ukhan
Tim Abbott
Alexander Trost
Eklavya Sharma
Umair Khan
Sumana Harihareswara