How to install and setup Snapraid

[@spediegunz]

I’m trying to understand how does parity data recovery work in snap raid Let’s say I have 3 20TB drives A(data) B(data) C(parity) If all drives are 20tb and drive B fails how does the parity drive have enough space to cover all the data in a and b at the same time ?

[@distrodomain]

When data is written, and after a sync, it will always have the correct parity, as it will have gone through various error-checking algorithms. That way, if a drive in the group fails, the system uses the information on the remaining disks along with the parity information to rebuild the data on the failed drive to a spare drive. It can figure out what was on the failed drive by adding up the bits on the remaining drives. If the data on the remaining drives adds up to an odd number, the information on the failed drive must have been a one to maintain even parity. If the data on the remaining drives adds up to an even number, the data on the failed drive must have been a zero.

[@scottie_oh]

How it was explained to me is imagine the entire array as an equation, let’s say 1 + 1 = 2. Each part of the equation is stored on a different drive, so if Drive B fails, we can recover because we still have the information on Drives A and C. In this case, the information we’d have is 1 + B = 2, therefor B must equal 1, so when the software rebuilds Drive B, it writes a 1.

[@scottie_oh]

Thanks for the video! I'm following along on Linux Mint 21.2. For anyone else using a Debian/Ubuntu-based distro, I replaced `dnf groupinstall "Development Tools"` with `apt install build-essential dh-autoreconf` and then I was able to follow the rest of the tutorial.

[@distrodomain]

Awesome thanks for the contribution!, I'm glad you were able to follow the tutorial, if you have any questions let me know

[@BMW750Ldx]

Thanks for the info 😉😉

[@prupdates1]

Super appreciated! Still new to Linux and I was wanting to stay on an OS I was familiar with, so this is exactly what I needed

[@MIKA-rz9fq]

Thanks man!! great video as usual!! 🤩

[@trapexit]

And it works well in combination with mergerfs ;)

[@distrodomain]

It's a perfect combo, indeed!

[@tandyman6672]

Thanks for another great tutorial! I really like your speed of presentation and the explanations you give along the way. ⭐⭐⭐⭐⭐

[@distrodomain]

I'm glad I'm able to help, thank you for watching!

[@YofuMedia]

amazing content...we want a studio tour!!!

[@PVPFTL]

Great video. Any chance you can add a video to the series showing the steps to remove and replace a failing drive?

[@distrodomain]

Great suggestion, I’ll make a video explaining the whole process!

[@PVPFTL]

@@distrodomain Great thanks!

[@mgarcianaval]

What's the filesystem? In the site they recommend ext4 or xfs. What filesystem do you prefere? Thanks

[@distrodomain]

I personally prefer xfs, I've used it in production environments and it's rock solid. thank you for watching :)

[@mgarcianaval]

@@distrodomain thank you very much :)

[@mgarcianaval]

I'm thinking in buy something from AliExpress. I really don't know if i install TrueNas Scale or OMV with Snapraid and merge the disks. I'm more inclined to choose the OMV to use in my home to me and my parents. I'm thinking in a Q1909M from Asrock or a i5 6500t. Low power consumption, but i'm glad to any suggestions. If do you have any hardware suggestions i'm pleased to know. Again thank you very much. Sorry for my English, i'm from Brazil.

[@distrodomain]

If you plan on scaling/upgrading the drives often and data is not data that changes often, snapraid is a better solution for this, if you plan on using this a backup and you are going to store data that are small files that change often truenas is a better option, what truenas lacks is flexibility and the fact tha you need to use same size drives. what are you planning on doing with the server.

[@distrodomain]

Check out my truenas video there I lay out some of the advantages and disadvantanges for this solution. kzbin.info/www/bejne/b2iTooedf9KKY5o

[@rosenfeldferenc5224]

My question would be How I choose parity disk. I have 6 disks. 2 times 120GB, 2 times 220GB, 1 time 160GB and 1 time 500GB. Thanks.

[@rosenfeldferenc5224]

After I tested conclusion is 2 times 120GB and 2 times 220GB is 680GB and 160 + 500 is 650 GB that can be parity together.

[@distrodomain]

Your parity drives should always be the same size or larger than any data drive, if your larget drive is 500gb that should be your parity drive if you only have 1 500 then is recommended to only have 1 parity drive, if you want 2 parity drives is recommended for them to be the same size. thank you for watching :)

[@TanjaPaetau]

💥👌👍

[@AgentMoler]

Is there a file system they recommend for this or does it not matter?

[@distrodomain]

I would recomend ext4 or xfs, those are pretty robust file systems, my preference being xfs, thank you for watching! :)