Manual:Store - prior to v6.20 release
Store manages storage devices used by RouterOS various facilities. For example Webproxy, User Manager and Dude could use external storage devices to store their files and databases. This is especially useful for RouterBOARD devices with SD/CF slots - as the built-in storage is quite small, an external drive comes in very handy when you want a big User Manager database.
You can add as many external or secondary drives as you want, and select any number of them for each of the mentioned feature use.
For example User Manager could be used on 3 disks, one of them would be the active database, and the rest would be backups.
You can then add a fourth disk, copy the active data to it - unplug it - and move to another server, to keep using the actual database.
This means migration and backup made easy!