First time (onboard) RAID setup help required.

[3pwood]

The parts:

 

Asus ROG Maximus X code,

seagate ST8000NE0004 Enterprise Nas hdd ( IronWolf Pro )*3

Samsung MZ-V6P1T0BW 1000Gb 960 Pro

 

Questions:

 

I've read that the m.2 shares bandwidth with 1 of the SATA ports so does this mean that in my RAID 5 setup I should avoid using the 1st SATA port? Just to be clear the point is to have the m.2 as my primary standalone drive and then the 3 SATA disks need to be setup in RAID 5.

 

I was hoping to avoid using forums for this question but after a few emails back and forth with ASUS support staff due to misunderstandings I got the attached response that just makes me feel that they really don't know what they're talking about.

 

 

[jj9987]

RAID 5 itself requires at least 4 drives, if you know how RAID 5 works. It can't be done with 3 drives.

If using M.2 means a SATA port gets disabled, then you need to use another port if you want to connect a drive.

[3pwood]

2 hours ago, jj9987 said:

RAID 5 itself requires at least 4 drives, if you know how RAID 5 works. It can't be done with 3 drives.

If using M.2 means a SATA port gets disabled, then you need to use another port if you want to connect a drive.

This is getting so confusing. The guides I read said 3 disk minimum, the storage calculators I used said 3 as well, I tested this by specifying 2 and it said you need a minimum of 3 disks for RAID 5...now some are saying I need 3 disks and others are saying 4. Even google says 3:

How many hard drives do you need for RAID 5?

The minimum number of disks in a RAID 5 set is three (two for data and one for parity). The maximum number of drives in a RAID 5 set is in theory unlimited, although your storage array is likely to have built-in limits. However, RAID 5 only protects against a single drive failure.

[KuJoe]

Avoid onboard (FakeRAID) at all costs, it's not worth the trouble.

 

As for RAID5, you are correct that 3 disks are the minimum required.

[Edelrat]

5 minutes ago, 3pwood said:

 

 

2 hours ago, jj9987 said:

 

You only need 3 drives for RAID 5, I don't know where that 4 drive thing comes from. Maybe people confuse it with RAID10 or RAID 6.

Regarding your SATA-port question: Read in your manual which SATA-port shares bandwith with the m.2 slot and don't use that one.

Just make sure to plug in all of the drives into the same controller (the Intel one preferably) , and that your controller is set to RAID-mode in the BIOS.

[3pwood]

38 minutes ago, KuJoe said:

Avoid onboard (FakeRAID) at all costs, it's not worth the trouble.

 

As for RAID5, you are correct that 3 disks are the minimum required.

Hmmm, I'll try to find pricing for RAID controllers in my country but I was really hoping to not have to install more expensive hardware than need be. I'll look into it though thanks.

[KuJoe]

1 minute ago, 3pwood said:

Hmmm, I'll try to find pricing for RAID controllers in my country but I was really hoping to not have to install more expensive hardware than need be. I'll look into it though thanks.

Use software RAID if you don't want to purchase a controller. As long as you're setting up the RAID on non-OS drives it should be simple and stable.

[3pwood]

37 minutes ago, MEOOOOOOOOOOOOW said:

 

You only need 3 drives for RAID 5, I don't know where that 4 drive thing comes from. Maybe people confuse it with RAID10 or RAID 6.

Regarding your SATA-port question: Read in your manual which SATA-port shares bandwith with the m.2 slot and don't use that one.

Just make sure to plug in all of the drives into the same controller (the Intel one preferably) , and that your controller is set to RAID-mode in the BIOS.

Yes I think they are getting it confused. I was just about to post a link to a LTT video explaining RAID 5 and 6, lol...but as you can see someone in this forum AND more importantly ASUS techs who you'd think would know their products say 4 disk minimum. If a RAID controller is too expensive for me (as suggested in previous post) then I'll do onboard RAID 5 and I'll first mess around with the different ONBOARD SATA ports to test speeds and functionality before populating the array.

[3pwood]

1 minute ago, KuJoe said:

Use software RAID if you don't want to purchase a controller. As long as you're setting up the RAID on non-OS drives it should be simple and stable.

I thought hardware RAID would be more reliable and robust than software but again I'll look into it. And yeah I'd never want my OS drive to sit on a RAID array, that just feels like asking for trouble hence me buying a 1TB m.2.

[KuJoe]

Hardware is normally better in all aspects, but if cost is a concern then software isn't a bad option. The only downside to using software RAID is that RAID5 will use more CPU to calculate the parity bit so hopefully you have some extra CPU cycles to dedicate to the RAID (the same would happen if you used the onboard RAID and some hardware RAID cards). If you're using Windows then setting up RAID5 is pretty simple and for your usage would most likely be plenty. If you're using Linux then setting up RAID5 is also simple and mdadm is really robust with some people opting to use it over a hardware RAID controller.

[jj9987]

1 hour ago, 3pwood said:

This is getting so confusing. The guides I read said 3 disk minimum, the storage calculators I used said 3 as well, I tested this by specifying 2 and it said you need a minimum of 3 disks for RAID 5...now some are saying I need 3 disks and others are saying 4. Even google says 3:

How many hard drives do you need for RAID 5?

The minimum number of disks in a RAID 5 set is three (two for data and one for parity). The maximum number of drives in a RAID 5 set is in theory unlimited, although your storage array is likely to have built-in limits. However, RAID 5 only protects against a single drive failure.

Crap, confused with RAID 6, my bad there. 3 is fine.

[3pwood]

6 hours ago, KuJoe said:

Hardware is normally better in all aspects, but if cost is a concern then software isn't a bad option. The only downside to using software RAID is that RAID5 will use more CPU to calculate the parity bit so hopefully you have some extra CPU cycles to dedicate to the RAID (the same would happen if you used the onboard RAID and some hardware RAID cards). If you're using Windows then setting up RAID5 is pretty simple and for your usage would most likely be plenty. If you're using Linux then setting up RAID5 is also simple and mdadm is really robust with some people opting to use it over a hardware RAID controller.

Well cost isn't a concern if I'm going to be using the onboard RAID though because technically I already have it. lol... I have heard about the downside of onboard RAID being more CPU cycles and also a bigger hit in write speeds? I've had 2 thoughts on this:

 

1. The videos I saw addressing all these were years old so I was hoping that with newer hardware a lot of the performance concerns would be mitigated?

2. I'm wanting a RAID setup for the parity because I'm tired of losing 2 or 3TB of data when I lose a drive. Now my usage case will be mainly as a media server so in my mind I wouldn't think write speeds OR the CPU cycles for parity would be that big a concern because I'm not going to be writing gigs and gigs of data to it everyday.

 

I could be wrong though and this is where posting to a forum comes in...to get opinions from others who have more experience with this kind of setup and usage?

 

[3pwood]

6 hours ago, jj9987 said:

Crap, confused with RAID 6, my bad there. 3 is fine.

Retard!!! No just kidding, lol...on the bright side you made me go back and read my emails to ASUS to ensure that I specified RAID 5 to them and I didn't accidentally type RAID 6...but I did say RAID 5 and even if I'd said RAID 6 their response should've then been to tell me that the board doesn't do RAID 6. lol.

[Electronics Wizardy]

On 2/1/2018 at 9:04 AM, KuJoe said:

Hardware is normally better in all aspects, but if cost is a concern then software isn't a bad option. The only downside to using software RAID is that RAID5 will use more CPU to calculate the parity bit so hopefully you have some extra CPU cycles to dedicate to the RAID (the same would happen if you used the onboard RAID and some hardware RAID cards). If you're using Windows then setting up RAID5 is pretty simple and for your usage would most likely be plenty. If you're using Linux then setting up RAID5 is also simple and mdadm is really robust with some people opting to use it over a hardware RAID controller.

Not better in all ways. You don't have bitrot protection with hardware raid. Expansion is much harder normally. Recovery is harder. 

[Electronics Wizardy]

On 2/1/2018 at 3:46 PM, 3pwood said:

Well cost isn't a concern if I'm going to be using the onboard RAID though because technically I already have it. lol... I have heard about the downside of onboard RAID being more CPU cycles and also a bigger hit in write speeds? I've had 2 thoughts on this:

 

1. The videos I saw addressing all these were years old so I was hoping that with newer hardware a lot of the performance concerns would be mitigated?

2. I'm wanting a RAID setup for the parity because I'm tired of losing 2 or 3TB of data when I lose a drive. Now my usage case will be mainly as a media server so in my mind I wouldn't think write speeds OR the CPU cycles for parity would be that big a concern because I'm not going to be writing gigs and gigs of data to it everyday.

 

I could be wrong though and this is where posting to a forum comes in...to get opinions from others who have more experience with this kind of setup and usage?

 

Cpu wise onboard raid also uses the cpu, so your won't be using any less cpu with software raid in windows. 

 

You need backups, not raid here. 

 

Storage spaces has horrible write speed with parity(about 40mB/s) Id suggest just using drive pool + snap raid. 

 

 

[KuJoe]

5 minutes ago, Electronics Wizardy said:

Not better in all ways.

Which is basically what I said.

[KuJoe]

7 minutes ago, Electronics Wizardy said:

You don't have bitrot protection with hardware raid.

Can you explain bit rot please? I Googled it but the explanation I am finding cannot be mitigated by software or hardware RAID.

[Electronics Wizardy]

1 hour ago, KuJoe said:

Can you explain bit rot please? I Googled it but the explanation I am finding cannot be mitigated by software or hardware RAID.

Data on a hdd will randomly flip over time(unlikey, but happens). Hardware raid will just give you the data as it has no idea this happened. Many software raid solutions(zfs, btrfs, refs, hammer) will checksum all writes and then if there during a scrub or read it will check it and repair it with the correct version stored on the parity or mirror.

 

Here is a nice level1 video