[twic]

> From the sysadmin viewpoint, /var is managed through "retention" (scheduled rotation, scheduled flushing, logrotate, crons, etc), and "backups" where needed.

Right. And 'Docker for /var' would be something that made all that easier. It would make it really easy to set up live, secure, restorable, backups of essential data; to rotate, compress, and delete logs; to extract all important logs to a separate host, and aggregate and index them, etc. At the moment, a configuration management tool can help you set this up, but you still have to write the configuration management script by hand.