Jump to content
Nanobug

Hardware vs Software RAID controller

17 posts in this topic Last Reply

Recommended Posts

Hello UnRAID forums.

I've decided to go with UnRAID for my NAS setup I'm planning, so I have some questions, which I'm posting in the different forum sections.

 

I know hardware RAID controller is better and more efficient since it's dedicated hardware for it.

But does it even work with UnRAID?

Also, which ones are good, at a decent price?

By a decent price, I'm thinking $100 or so.

Share this post


Link to post

Unraid is NOT RAID. 

RAID controllers are NOT recommended and can cause problems. 

Share this post


Link to post
44 minutes ago, trurl said:

Unraid is NOT RAID. 

RAID controllers are NOT recommended and can cause problems. 

So I can't even use RAID 0 to gain extra speed?

Share this post


Link to post
8 minutes ago, trurl said:

Various configurations of btrfs raid are available in the cache pool.

 

For a better idea of how Unraid differs from traditional RAID, see the Product pages and this wiki overview:

 

https://wiki.unraid.net/UnRAID_6/Overview

I'm mainly planning on using it as a Media Server, so I need efficiency, therefor RAID 0 and or RAID 1+0.
That's also why I was planning on using a hardware RAID controller, for even more efficiency.

Share this post


Link to post
6 minutes ago, Nanobug said:

I'm mainly planning on using it as a Media Server

Unraid was designed to be a media server and that is how most people use it.

 

I recommend reading the material I mentioned and then you will be able to ask better questions.

Share this post


Link to post
Just now, trurl said:

Unraid was designed to be a media server and that is how most people use it.

 

I recommend reading the material I mentioned and then you will be able to ask better questions.

I did look at it, before and after you linked it to me.

It's just a bit difficult when English isn't my first language, that's why I was asking.

Share this post


Link to post

I'm not trying to find to be lazy, annoying or anything like that. I'm trying to understand it, so I can make a decision on what hardware to buy, or not to buy.

Share this post


Link to post

Unraid doesn't have the speed of traditional RAID, and realtime parity updates make write speed even somewhat slower than single disk writes. Unraid makes these tradeoffs to get several other benefits which actually work well for media servers in a home environment.

  • Mix disk sizes. You don't have to have all disks the same size.
  • Add additional disks without rebuilding the array.
  • Each disk is a completely independent filesystem. There is no striping. If you lose more disks than parity can recover from, you don't lose everything, only the affected disks.
  • Even though each file is completely on a single disk, folders can span disks.
  • Disks not in use can spin down.

Read speed from the array is always at the speed of a single disk, since there is no striping. For more details about how writing to the parity array works, see here:

 

https://forums.unraid.net/topic/50397-turbo-write/

 

Unraid also supports a btrfs raid cache pool, which allows raid0, raid1, raid10, raid5, raid6. See the Cache Pool section of the FAQ for more details:

 

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/page/2/?tab=comments#comment-554741

 

People use the cache pool for faster writes that are later moved to the slower, larger parity array.

 

Unraid can host VMs and docker applications. People install VMs and docker applications on cache to get better performance of their applications, and so their applications will not keep parity and array disks spinning.

 

Share this post


Link to post
5 hours ago, trurl said:

Unraid doesn't have the speed of traditional RAID, and realtime parity updates make write speed even somewhat slower than single disk writes. Unraid makes these tradeoffs to get several other benefits which actually work well for media servers in a home environment.

  • Mix disk sizes. You don't have to have all disks the same size.
  • Add additional disks without rebuilding the array.
  • Each disk is a completely independent filesystem. There is no striping. If you lose more disks than parity can recover from, you don't lose everything, only the affected disks.
  • Even though each file is completely on a single disk, folders can span disks.
  • Disks not in use can spin down.

Read speed from the array is always at the speed of a single disk, since there is no striping. For more details about how writing to the parity array works, see here:

 

https://forums.unraid.net/topic/50397-turbo-write/

 

Unraid also supports a btrfs raid cache pool, which allows raid0, raid1, raid10, raid5, raid6. See the Cache Pool section of the FAQ for more details:

 

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/page/2/?tab=comments#comment-554741

 

People use the cache pool for faster writes that are later moved to the slower, larger parity array.

 

Unraid can host VMs and docker applications. People install VMs and docker applications on cache to get better performance of their applications, and so their applications will not keep parity and array disks spinning.

 

Thank you. That was helpful. I've saved those links.

I have a question though. Will I be able to use a cache for Steam games for example? So when there's an update to a Steam game, Steam will look at the cache first and update it from there, instead of getting it from a Steam Server?

Share this post


Link to post
1 hour ago, Nanobug said:

Thank you. That was helpful. I've saved those links.

I have a question though. Will I be able to use a cache for Steam games for example? So when there's an update to a Steam game, Steam will look at the cache first and update it from there, instead of getting it from a Steam Server?

Hi there,

 

A basic google search of setting up a steam cache will show you how to do this.  As far as where that cache "lives" in Unraid, I would recommend just letting it live in the array.

 

With respect to your original post, I'm not sure what your obsession with RAID 0 is exactly if all you're looking to do is set up a basic media server.  First and foremost, your max speed to accessing data on the NAS will be capped at your network speed.  Most networks are still at 1gbps, so unless you're packing 10gbps networking (which I doubt), your max speeds for accessing data on the system will be ~ 100MB/s.  That's slower than any average modern HDD anyway.  SO all you get with RAID 0 is increased capacity at the cost of a higher probability for critical failure and loss of data (since there is no redundancy in RAID 0 anyway).

 

So my recommendation for you is to not worry about hardware RAID or even RAID 0.  Just set your server up with HDDs for the array and if you want to add a little performance, you can add an SSD or dedicated HDD for the cache.  To maximize performance, go to the Disk Settings page (Settings > Disk Settings) and toggle the write method to reconstruct/write.  This will increase general write speed to the array (at the cost of keeping all your disks spinning during a write operation).

Share this post


Link to post
10 hours ago, jonp said:

Hi there,

 

A basic google search of setting up a steam cache will show you how to do this.  As far as where that cache "lives" in Unraid, I would recommend just letting it live in the array.

 

With respect to your original post, I'm not sure what your obsession with RAID 0 is exactly if all you're looking to do is set up a basic media server.  First and foremost, your max speed to accessing data on the NAS will be capped at your network speed.  Most networks are still at 1gbps, so unless you're packing 10gbps networking (which I doubt), your max speeds for accessing data on the system will be ~ 100MB/s.  That's slower than any average modern HDD anyway.  SO all you get with RAID 0 is increased capacity at the cost of a higher probability for critical failure and loss of data (since there is no redundancy in RAID 0 anyway).

 

So my recommendation for you is to not worry about hardware RAID or even RAID 0.  Just set your server up with HDDs for the array and if you want to add a little performance, you can add an SSD or dedicated HDD for the cache.  To maximize performance, go to the Disk Settings page (Settings > Disk Settings) and toggle the write method to reconstruct/write.  This will increase general write speed to the array (at the cost of keeping all your disks spinning during a write operation).

Thank you for clarifying.

Is it possible to do with other clients, like battlenet, Origen, GoG Galaxy etc.?

Share this post


Link to post

Honestly no idea.  I've never tried.

Share this post


Link to post
9 minutes ago, jonp said:

Honestly no idea.  I've never tried.

Alright. I will look into it when I've set up the system. Thanks :)

Share this post


Link to post

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.