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mamr

Member

Registered: 2008-08-16

Posts: 63

Benefits of using BTRFS for external backup HDDs?

I've been using BTRFS on my laptop's internal SSD for a while without any problems. Recently I stumbled across an article on ArsTechnica praising BTRFS.

My backup system at the moment consists of using LUKS encrypted external HDDs in combination with rsync and I'm perfectly fine with that. I have a special folder on these HDDs, where deleted files get stored (rsync's options -b and --backup-directory) and I don't think I need a more complicated "snapshot structure" than that.

I know that BTRFS is a young file system and might contain bugs but I want to leave that aside for a moment. I know of the snapshot features (I don't use them on my laptop either) and the send/receive features of BTRFS but I don't think I would need those. Apart from that I'm just curios: are there any other benefits from using BTRFS although I don't have a RAID setup? I am particularly interested in preventing bitrot (with checksumming). As far as I understand I need a RAID setup to really use this feature. I tried to look-up this question on the Internet but didn't understand enough. Does anyone of you use BTRFS for backup?

Last edited by mamr (2014-12-26 10:23:09)

Soukyuu

Member

Registered: 2014-04-08

Posts: 854

Re: Benefits of using BTRFS for external backup HDDs?

The bitrot prevention isn't really that different from other FS from what I understand. The only thing different is convenience - while I have to run md5sum to check the .md5 of my files of my NTFS backups, I'd simply have to run btrfs scrub on the volume for btrfs. And since all files have their checksums per default, you don't have to manage/update them at all.

Another thing is that depending on how many binary duplicates you have, you could save some space with btrfs' deduplication, but it's a manual one at the moment.That said, duplicated files are rare on backups, so I'm not sure if this feature is relevant at all.

Last edited by Soukyuu (2014-12-26 12:47:35)

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graysky

Wiki Maintainer

From: :wq

Registered: 2008-12-01

Posts: 10,600

Website

Re: Benefits of using BTRFS for external backup HDDs?

I would not recommend using BTRFS for a reliable backup.  In my experience and opinion, it is too new and unproven compared to other options like ZFS for example (assuming you're using 3+ disks).  I say this having suffered a data loss on BTRFS due to an ungraceful shutdown.  Stick with something established for critical data in this report's option.

EDIT: added link.

Last edited by graysky (2014-12-26 20:01:12)

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nstgc

Member

Registered: 2014-03-17

Posts: 393

Re: Benefits of using BTRFS for external backup HDDs?

I second Graysky's opinion, I have back ups in case btrfs messes up. Additionally, the checksums don't help with bit rot much unless it is being run in a RAID with redundancy.

WonderWoofy

Member

From: Los Gatos, CA

Registered: 2012-05-19

Posts: 8,414

Re: Benefits of using BTRFS for external backup HDDs?

I third graysky's opinion.  Though I think at times he can be a bit quick to absolutely tell people it is no good, I do think that for a backup solution it is a bad bad idea.  I use btrfs as th filesystem on my daily driver laptop, but I would never use it as my backup solution unless I had backups for those backups.