Maximum HDD Size for Pegasus2 R4

  • Last Post 14 January 2024
David Ledger posted this 07 December 2023

Thought id create this post for anyone interested.

I was looking to upgrade the HDD's in my R4, so went for 4 x Seagate EXOS Enterprise 8TB drives. Found them for a great price.

About a week ago I set them up in RAID 5. It took about 24 hours for the disks to synchronise, and I now have 24tb of useable storage space.

My blackmagic disk speed checker gave me between 700-800 write, and around 600-700 read, and I'm delighted to find that it has worked flawlessly in Resolve and Final cut with 4k Prores 422 content.  (I've been editing alot over the past week)

Im currently running an M1 Max Macbook Pro via an Apple Thunderbolt 2 to 3 adapter cable too. (I know some people have been concerned about compatibility with Apple Silicon. Updating to the latest firmware and drivers has done the trick)

If i encouter any problems I will be sure to post about it here. 

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R P posted this 11 December 2023

Hi David,

Promise has a list of drives that were tested with the Pegasus2. It's called the compatibility list.

A few notes.

1. Many disks listed are no longer in production. With respect to the maximum size supported, this does not matter, if a 10TB disk was tested, then you know that other 10TB drives won't fail for being too large.

2. It's best for drives in a RAID configuration to be the same, but you don't want to get a 10 year old drive of the same model off EBAY. So the next best thing is to use a same size drive from the same manufacturer. Failing that, then the same size drive from a different manufacturer.

3. I'd be most concerned if the drive is substantially larger than the largest drive tested. If they come out with 50TB drives next year, I'd strongly expect some issues with the Pegasus2, potentially serious issues. The latest hardware (Pegasus32) is most likely to support tomorrow's larger drives.

Travis Winn posted this 09 January 2024

I am super interested, thanks for posting this.  I am hoping to use it for a bigger hard drive, I have never set up a RAID drive before and have it coming soon.  Thanks for posting.  I am going to be trying for the 10 TB Hard Drives when it comes from Ebay soon.  Will try to keep posted.


Travis Winn posted this 09 January 2024

Hi David,

Since I am new to this I was wondering, so if you set them up in RAID 5  all the same that is 8 x 4 = 32 TB so with the RAID 5 configuration you get 24 TB of useable space?  Does that work out, how backed up is everything in this scenario, I am contemplating going 10 x 4 as that seems to be the maximum you can get. Thanks.  Also, I just got my new drive from ebay and the 4 x 4 HDs is showing up as 12 TB which is what it should be it seems. 

R P posted this 10 January 2024

Hi Travis,

so if you set them up in RAID 5  all the same that is 8 x 4 = 32 TB so with the RAID 5 configuration you get 24 TB of useable space?

No. RAID5 distributes 1 disk's worth of parity among all the disks, so subtract one disk, 32TB - 4TB = 28TB

Does that work out, how backed up is everything in this scenario

There is a saying in the storage industry, RAID is not a backup solution. But you can lose any one disk and your data will still be online.

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Travis Winn posted this 14 January 2024

Thanks for the feedback, I am liking the speed, but still need to buy 4 new drives that will probably either be 8tb each or 10tb each.