RAID1 Time Capsule mirror

If you simply want a second (or more) copy of your TimeMachine backup data on a second drive for redundancy, TimeMachine will do that for you directly. No need for a RAID. You can alternate backups between two (or more) destinations.

TimeMachine will also include attached external drives in the backup if set up to do so.

I use both a time capsule and attached drive sized large enough for both the internal and external working drive. In the time machine settings I add the two destinations. Attached external drive are excluded by default but you can change that under the "options" menu. I exclude only the local backup drive.

Works well. I think the feature was introduced in 10.8... but I dunno. So many of the older guides won't mention it.

You can use something like CCC to do the same thing and with more flexibility. Much less money than a RAID box. RAID is more useful if you need much more performance than a single drive can provide or a massive amount of storage (>5TB) in a single box/disk. Thats not the case for backups for a couple machines, unless you have massive amounts of data to backup.

 

I don't like RAID for backups as when one drive dies (when not if), the array sometimes cannot be rebuilt and you lose data. Looking at an NAS is what you want to do!

 

Although many here have has some luck with NASs other than Apple approved devices, if the OP is using TimeMachine to back up to a networked device, he should stick to a Time Capsule.

He can think about connecting a larger USB drive to his current time capsule or replace the current TimeCapsule with one of the newer 2TB or 3TB models.