Have you seen the Drobo box? it’s a SAN that allows you to create giant volumes and hot swap out hard drives at will with failure tolerance… bad news, is that it costs close to £1000 even without the drives, i’ll explain how to make a better one… for free! =).

ZFS (Zettabyte Filing System) is Sun’s newest file-system offering, its supported on FreeBSD / Solaris natively and Mac OS X / Linux / Windows via third-party utilities. I’m gonna keep this guide, simple, short and sweet, so i’ll bullet list the main features that wow people about ZFS =)

• It can store up to 340 quadrillion zettabytes of data (no other production filing system can do this)
• It checksum’s your data on the fly so you can check for integrity by “scrubbing” it (identifying broken drives before they completely die)
• It supports every raid configuration you can think of natively and doesn’t suffer from the raid5 data-hole.
• You can create snapshots of your data that do not waste hdd capacity.
• Volumes or “Pools” can be expanded at any time, so you can start with a 2tb raid, and increase it to a 10tb raid with no data loss.
• You can mix/match capacities, brands, rpm’s of drives.
• Its reliable* (on officially supported incarnations anyway)
• Its a memory whore (don’t try it unless you have 2gb ram on your system)
• Its supported in the latest version of FreeNAS (0.7)
• Allows hotplugging of drives when one fails (so you don’t lose data/time)
• Hotspares are supported
• Can be easily transferred / transported to any other ZFS supported system without extensive configuration or any data loss.
• Its free free free free (under CDDL).

Think of a hardware raid5 or a geom_concat/raid and then think about those again, but without any of the issues / flaws they have… thats what ZFS is! =)

So lets get started, I’ll run through creating and bringing a ZFS raid online first, and then some maintenance commands afterwards. I suggest trying this on a Continue reading →