Linux Repository | which filesystem

[thomas23]

Hello veeam-users,

we plan a new place for hold our backup repository and And we want to use linux. There are differences
which filsystem should we use for the direct attached storage (performance vs stability?
I prefer a CentOS or Debian System, but the main-question is ext4,btrfs,ZFS ....
Today we use version 9.5.

Thanks in advance
Thomas

[mkretzer]

I have the same question - I hope that at some point something like refs block clone works with btrfs or so. What is the most future prove fs?

[nitramd]

I had the good fortune and pleasure to attend VeeamON 2017. I attended one of Anton Gostev's breakout sessions, which was on the topic of Backup Repository Best Practices. His personal recommendation for a Linux file system is XFS; developed by SGI. It's been around for ~25 years and has never had a crash in over 20 years.

You can check out the XFS website @ xfs.org; be sure to look at the FAQ. You can also check Red Hat's article on file system limitations here: https://access.redhat.com/solutions/1532 - good read.

As you may be aware, the current release of CentOS 7 defaults to the XFS filesystem.

Hope this helps.

-MD

[mlott@gie.com]

We use XFS for our file server and generally for anything that would require more than 16TB of storage. We also use it for smaller than 16TB. The failures I have seen with this file system were only when there was a problem with the underlying array, etc. In those extreme cases, you can end up with some zero-length files and other weirdness. I recommend it but I wouldn't say it's indestructible.

[nitramd]

Sorry, should have been more clear. The comments with regards to the XFS filesystem, i.e. how long its been around, etc, were made by Anton at the breakout session; this is my recollection of what he said about XFS.

I believe that he was trying to show that XFS is a proven technology due to its longevity and robustness.

I also know of no bulletproof computer hardware or software but certainly recommend XFS.

[Gostev]

Yes, I can confirm I did say that of course, while it was more of a joke to get the point across - the reason for one was that I've never heard anything but praise on XFS stability and reliability.

[thomas23]

Hello together,

i wonder, that nobady talk about btrfs. Behind the question, it stands the hope that we see some integration in filesystem-functionality (in the future).
Anyway, I'll test first with xfs.

thanks
Thomas

[Gostev]

Because simply put, btrfs is a terrible choice these days (way too unreliable, needs to mature first). Definitely the last place you want to be using for storing your backups.

[dellock6]

To better answer, BTRFS instability should be split into two different parts:
- file structure is totally stable, has not been changed for a long time, and it's proven in multiple places (its lead developers work at Facebook and they use it in many places, and Suse is using now btrfs as their default filesystem)
- userland tools is were development is still rapidly changing, and some tools and options are not stable yet. You can have a better view on the current status here: https://btrfs.wiki.kernel.org/index.php/Status

Do you need specifically some of the feature that BTRFS has? If no, then you are ok with XFS. I'd go for XFS myself probably "today", but who knows in one year.

[Robvil]

I´m running on btrfs without issues.

[davecla]

Anyone using ZFS??
I've migrated my repositories to ReFS which seems to work really well, but was thinking seriously about moving to ZFS on Linux to give OS separation. I've just had 600TB of Dell JBOD delivered - waiting for the linux guys to do their bit, then it's all go, so very keen to hear about others experiences in this space.

[Gostev]

ZFS is fine. It is quite popular file system for backup repositories, especially among our service providers. I recommend both XFS and ZFS without hesitation, but prefer XFS for maturity and reliability.

[nitramd]

@davecla,

If you're interested, check out the following ZFS links on the FreeNAS website; these documents may help to illuminate ZFS:

FreeNAS® User Guide 9.10.2-U2: http://doc.freenas.org/9.10/

FreeNAS: A Worst Practices Guide: http://www.freenas.org/blog/freenas-worst-practices/

Although I don't use ZFS, I find it quite intriguing and may have to setup a test environment sometime down the road.

-MD