Before we deploy this commit, we must migrate the data from the staging redis
server to the new, dedicated redis server. The steps for doing so are the
following:
* Remove the zulip::redis puppet class from staging's zulip.conf
* ssh once from staging to redis-staging.zulip.net so that the host key is known
* Create a tunnel from redis0.zulip.net to staging.zulip.net
* zulip@redis0:~$ ssh -N -L 127.0.0.1:6380:127.0.0.1:6379 -o ServerAliveInterval=30 -o ServerAliveCountMax=3 staging.zulip.net
* Set the redis instance on redis0.zulip.net to replicate the one on staging.zulip.net
* redis 127.0.0.1:6379> slaveof 127.0.0.1 6380
* Stop the app on staging
* Stop redis-server on staging
* Promote the redis server on redis0.zulip.net to a master
* redis 127.0.0.1:6379> slaveof no one
* Do a puppet apply at this commit on staging (this will bring up the tunnel to redis0)
* Deploy this commit to staging (start the app on staging)
* Kill the tunnel from redis0.zulip.net to staging.zulip.net
* Uninstall redis-server on staging
The steps for migrating prod will be the same modulo s/staging/prod0/.
(imported from commit 546d258883ac299d65e896710edd0974b6bd60f8)
Zev Benjamin