20
RAID array filesystem recommendations
(sopuli.xyz)
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
this post was submitted on 10 Nov 2024
20 points (95.5% liked)
Selfhosted
40219 readers
964 users here now
A place to share alternatives to popular online services that can be self-hosted without giving up privacy or locking you into a service you don't control.
Rules:
-
Be civil: we're here to support and learn from one another. Insults won't be tolerated. Flame wars are frowned upon.
-
No spam posting.
-
Posts have to be centered around self-hosting. There are other communities for discussing hardware or home computing. If it's not obvious why your post topic revolves around selfhosting, please include details to make it clear.
-
Don't duplicate the full text of your blog or github here. Just post the link for folks to click.
-
Submission headline should match the article title (don’t cherry-pick information from the title to fit your agenda).
-
No trolling.
Resources:
- selfh.st Newsletter and index of selfhosted software and apps
- awesome-selfhosted software
- awesome-sysadmin resources
- Self-Hosted Podcast from Jupiter Broadcasting
Any issues on the community? Report it using the report flag.
Questions? DM the mods!
founded 1 year ago
MODERATORS
Could you elaborate on btrfs on top of md raid?
This one seems the most likely solution for me.
Sure. First you set up a RAID5/6 array in mdadm. This is a purely software thing, which is built into the Linux kernel. It doesn't require any hardware RAID system. If you have 3-4 drives, RAID5 is probably best, and if you have 5+ drives RAID6 is probably best.
If your 3 blank drives are sdb1, sdc1, and sdd1, run this:
mdadm --create --verbose /dev/md0 --level=5 -n 3 /dev/sdb1 /dev/sdc1 /dev/sdd1This will create a block device called /dev/md0 that you can use as if it were a single large hard drive.
mkfs.btrfs /dev/md0That will make the filesystem on the block device.
This creates a mount point and mounts the filesystem.
To get it to mount every time you boot, add an entry for this filesystem in /etc/fstab
Do you need to do some maintenance to keep the data in the array intact?
I read of some btrfs scrub commands and md checks and such, but I am unsure how often to do them, and what they actually do.
You should scrub your data regularly with btrfs. That's just a mean to verify the data is in-tact though; to detect corruption.
You cannot really do anything actively to keep the data in-tact. Failure can and will happen. To keep your data safe, you must plan for failure to happen:
Expect a power surge to fry all your disks at the same time.
Expect your house to burn down or flood.
Expect to run the wrong command and istantly hose your entire array.
Expect your backup server to get ransomware'd.
...
Only if you effectively mitigate these dangers will your data stay safe.