Hello all,

i am a Synology user who is exploring the possibilities. In case i will change the Synology brand to UGREEN NASync DXP8800 Plus 8-Bay. Will i be able to deploy UNRAID? (still awaiting reply from uGreen co).

In case of yes, will i be ablet to first e.g. 4x 24TB WD RED Pro disks in RAID 5, and then later extend by additionally 4 same disks. Does UNRAID offers an alternative to Synology SHR or does RAID 5 has his option? Without loosing data while rebuilding an Array?

What is the best approach?

Thank you

M

Unraid supports array and pools, array can easily be expanded, btrfs pool as well but raid5 is not recommended with btrfs, zfs pools can now also be expanded, but for now, only using the CLI

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/page/4/#findComment-1537164

Hello Jorge,

thanks for your quick reply to my post. In other words, there is a simple ways to expand the existing volume by additional extra added disks without rebuilding the array from scratch and losing all data (or being forced to move the data elsewhere. Not mentioning the recommended best practices of course).

Thanks

Martin

36 minutes ago, marsim_ms said:

there is a simple ways to expand the existing volume by additional extra added disks without rebuilding the array from scratch and losing all data

Correct, especially with the array, it's much more flexible, the main negative point is performance, since the disks are not striped, more info below:

https://forums.unraid.net/topic/131857-soon%E2%84%A2%EF%B8%8F-612-series/?do=findComment&comment=1243850

OK does that mean, that if i will build an array e.g. with 4 disks, then later adding 4 another (of the same model and size) , those new ones wont be then striped together with those first 4 disks, correct?

Would it be like:

8bay NAS - RAID 5:

• 1st stage: 4 disks striped

• 2nd stage: adding another new additional 4 disks, but they will be striped also group of 4 disks?

Its also good to know up front what will be the consequence of such setup, if its the dead end or the striping OR could it be expanded from 4 disks to 8 disks later? Or not

Thanks

Edited July 31, 2025Jul 31 by marsim_ms

The array in Unraid runs like individual disks without striping data. This allows you to add one disk at a time. In fact they dont even have to be the same size as long a the parity drive is the equal or greater to the largest drive. What your suggesting above would be a 4 disk striped pool (zfs usually) and then you could add 4 identical disk to expand the pool. The downside to the array like JorgeB stated is the performance is based on a single disk since the data is not stripped. You can set it up either way based on your use case. Most around here use the array option for the flexibility since most are just media servers.

Edited July 31, 2025Jul 31 by Gragorg

1 hour ago, Gragorg said:

The array in Unraid runs like individual disks without striping data. This allows you to add one disk at a time. In fact they dont even have to be the same size as long a the parity drive is the equal or greater to the largest drive. What your suggesting above would be a 4 disk striped pool (zfs usually) and then you could add 4 identical disk to expand the pool. The downside to the array like JorgeB stated is the performance is based on a single disk since the data is not stripped. You can set it up either way based on your use case. Most around here use the array option for the flexibility since most are just media servers.

Ahh ok, i am then getting to the finish line. I still did not understand the part about my case.

This case will work generally with array RAID 5:

Option 1 - 8bay NAS - RAID 5

• 1st stage: 4 disks striped with parity in RAID5

• 2nd stage: adding another new additional 4 disks , but they will be striped also as separated group of 4 disks?

OR

Option 2 - 8bay NAS - RAID 5:

• 1st stage: 4 disks striped with parity in RAID5

• 2nd stage: adding another new additional 4 disks, and they will be striped together with previously first striped 4 disks?

Trying to understand the possible concept. Otherwise do i have to ONLY build an array and strip the alll 8 disks in on go? If other workaround would not be possible. Want to have also performance

And in such case i might be the target customer for unRAID than (maybe). Was not aware that unRaid does not provide striping function

Edited July 31, 2025Jul 31 by marsim_ms

Currently using zdev pools I believe Option 1 is what is supported. Zdev expansion will be added when Open ZFS 2.3 is added to Unraid. I haven't been paying attention if this has happened yet as I dont use zdevs.

Raidz expansion is supported since Unraid 7.1 using the CLI, since 7.2 single raidz vdev pools can be expanded using the GUI.