Postgres Dockerfile

Docker image for Postgres 9.4 + WAL-E + PL/Python and PL/V8 languages

Basic usage

$ docker run -p 5432:5432 abevoelker/postgres
2014-07-31 06:11:07 UTC LOG:  database system was shut down at 2014-07-31 05:52:53 UTC
2014-07-31 06:11:07 UTC LOG:  database system is ready to accept connections
2014-07-31 06:11:07 UTC LOG:  autovacuum launcher started

WAL-E usage

This image comes with WAL-E for performing continuous archiving of PostgreSQL WAL files and base backups. To use WAL-E, you need to do a few things:

1. Create a directory with your secret environment variables (e.g. your AWS secret keys) in envdir format (one variable per file) and mount it as a volume overwriting /etc/wal-e.d/env when calling docker run.

2. Edit your postgresql.conf archive settings to use WAL-E. Changes should look something like this:

wal_level = archive # hot_standby is also acceptable (will log more)
archive_mode = on
archive_command = 'envdir /etc/wal-e.d/env wal-e wal-push %p'
archive_timeout = 60

3. Mount a volume to /etc/cron.d with a crontab for running your periodic WAL-E tasks (e.g. full backups, deleting old backups). Here's an example that does a full backup daily at 2AM and deletes old backups (retaining 7 previous backups) at 3AM:

PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
0 2 * * * postgres envdir /etc/wal-e.d/env wal-e backup-push /var/lib/postgresql/9.4/main
0 3 * * * postgres envdir /etc/wal-e.d/env wal-e delete --confirm retain 7

4. Run the container with /sbin/my_init instead of the default command. This is necessary to start cron, syslog, and Postgres. In this mode, runit manages the cron and Postgres processes and will restart them automatically if they crash.

Example docker run that covers basic WAL-E usage:

$ ls -1 /tmp/env
AWS_ACCESS_KEY_ID
AWS_SECRET_ACCESS_KEY
WALE_S3_PREFIX
$ ls -1 /tmp/cron
wal-e
$ cat /tmp/cron/wal-e
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
0 2 * * * postgres envdir /etc/wal-e.d/env wal-e backup-push /var/lib/postgresql/9.4/main
0 3 * * * postgres envdir /etc/wal-e.d/env wal-e delete --confirm retain 7
$ docker run -v /tmp/env:/etc/wal-e.d/env -v /tmp/cron:/etc/cron.d abevoelker/postgres /sbin/my_init
*** Running /etc/rc.local...
*** Booting runit daemon...
*** Runit started as PID 13
2014-07-31 06:11:07 UTC LOG:  database system was shut down at 2014-07-31 05:52:53 UTC
2014-07-31 06:11:07 UTC LOG:  database system is ready to accept connections
2014-07-31 06:11:07 UTC LOG:  autovacuum launcher started

License

MIT license.