The How-To Geek Forums Have Migrated to Discourse

How-To Geek Forums / Apple / OS X

Raid 1 Mirror Out of Sync..suggestions please!

(3 posts)
  • Started 9 years ago by MikeB
  • Latest reply from MikeB
  • Topic Viewed 5672 times

Posts: 2

Hi guys,

I've been using 2 x 500GB WD MyBooks set up as a Raid 1 Mirror for a few months. I've had to rebuild one of the drives a few times as they go out of sync very easily. I located the problem to be the power supply which I rectified but I knocked the power out of one the other day and they're out of sync again.

My question: Is there any way to re-sync the drive without having to go through the 9hour rebuild process that my macbook has built into the disk utility? The data stored is still exactly the same on each drive. Seems stupid to have to go through this process on a regular basis.

Any info will be much appreciated.

Many thanks.

Posted 9 years ago
The Geek
Posts: 2059

Typically raid sets are supposed to be close together, and not be powered off at any point. Once the drive has powered down, then the operating system doesn't know whether or not the drives are still in sync, so it has to do a full rebuild.

It really shouldn't take quite that long... are they both externals?

What I'd do, personally, is keep both drives as separate drives, and use rsync to sync one drive to another. (In fact that's exactly what I do with my linux box) rsync wouldn't have the problems you are having.

Posted 9 years ago
Posts: 2

Hi thanks for your quick response. Yes they are both externals and sit side by side on my desk powered by a multi-socket and aren't usually unplugged, if they are then they are unplugged together.

Thanks for the link to rsync, I'll give that a go next time. I left my machine on over night and 9 hours later the slice is now online again. I was kinda hoping that there was some sort of raid manager that could look after it but a quick google didn't turn up much unfortunately.

Many thanks again.


Posted 9 years ago

Topic Closed

This topic has been closed to new replies.