NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.

Forum Discussion

jimk1963's avatar
jimk1963
Luminary
Dec 22, 2023

Use external SATA cloning dock to expand NAS

My RN528 came with 8x4TB Toshiba HDD’s. Using X-RAID I have about 21TB of usable space (if memory serves, might be a little higher). Presently about 10TB is populated.

 

Considering swapping in 4 16TB drives (Exos X16/18/20 or Ironwolf Pro, just depends on best deal I can find). My understanding is RAID 6 requires at least 4 disks to be swapped to see the expanded capacity.

 

I understand one upgrade method is to swap out a single drive, wait for resync, swap out the second drive, wait again for resync, and so on. Having gone through a few same-capacity drive swap-outs with various NAS’s (including this one), I found the resync time to be very long. I think the last one I did took more than a day.

 

Also read advice on this forum to run Seatools on new drives to confirm error-free status before committting them to the NAS. This led me to look at external SATA docking stations (typically USB 3.1 Gen 1 or Gen2) as an easy way to mount drives without having to open my desktop tower. Example:

 

https://sabrent.com/products/ec-hd2b

 

I see that these docking stations perform cloning. So my question is, instead of trudging through resyncs x 4, is it technically feasible to clone each 4TB drive (say, drives 1 through 4) to 4 new 16TB drives, and then simply install the new 16TB drives without any subsequent rebuilding or other “work” on the part of the NAS? 

Alternatively, if I had a 4-bay external SATA dock, could I just install the four 16TB drives in it and copy the entire NAS over to these larger drives, and then swap out the first 4 4TB drives with the 16TB’s? I’m guessing this wouldn’t work at all, but am not sure.

7 Replies

  • The tradeoff here:

     

    Hotswapping 4 disks one at a time will certainly take more time.  But the NAS remains in service throughout the process (though the performance won't be as good as usual).  

     

    There are alternatives that will complete more quickly, but the NAS will be down while you are doing them, and they have a lot more manual steps.

     

    So one obvious question is why you need to hurry.  You are using only 50% of the NAS storage today, so there is no urgent reason to expand.

     

    Also, it sounds like you have no backup plan in place for the NAS.  RAID (even dual redundancy) isn't enough to keep your data safe.  Personally I would take care of that before thinking about expansion. 

     

    One option is to purchase a 5th 16 TB drive and use it to back up your data. Then add additional backup disks as the capacity grows.  You could put this fifth drive into a suitable enclosure and connect it to a PC (doing the backups over the network). I've gone with a different approach myself - backing up to other NAS.  While more expensive to set up, it is easy to fully automate and easy to expand as my storage grows.  

     

    FWIW, I have a similar model to the Sabrent you linked (mine has USB-C cabling) that I picked up a couple of years ago.  I've had no issues with it.   It is suitable for temprary use (cloning, disk testing, disk erasing, etc). But it not the best choice for more permanent use (like backup), since the disks aren't secured in place.  You'd want something where the disks can't be accidently disconnected.  

     

     

     


    jimk1963 wrote:

    My RN528 came with 8x4TB Toshiba HDD’s. Using X-RAID I have about 21TB of usable space (if memory serves, might be a little higher). Presently about 10TB is populated.

     


     

     

    The NAS reports space in TiB but labels it as TB (same as Windows).The capacity rule for dual redundancy is sum the disks and subtract the largest two.

     

    Your current capacity is 24 TB (~21.8 TiB).  4x16 + 4x4 will give you 48 TB (~43.7 TiB), so twice the space.

     


    jimk1963 wrote:

     

    I understand one upgrade method is to swap out a single drive, wait for resync, swap out the second drive, wait again for resync, and so on. Having gone through a few same-capacity drive swap-outs with various NAS’s (including this one), I found the resync time to be very long. I think the last one I did took more than a day.

     


    It takes a while because every sector in the volume is either read or written during the each replacement.

     

    So 32 TB of I/O for each of the first three replacements. The fourth disk will take more twice as long, since due to the expansion you will have 80 TB of I/O.  Total I/O for all four then is 176 TB.

     


    jimk1963 wrote:

     

    Alternatively, if I had a 4-bay external SATA dock, could I just install the four 16TB drives in it and copy the entire NAS over to these larger drives, and then swap out the first 4 4TB drives with the 16TB’s? I’m guessing this wouldn’t work at all, but am not sure.


     

    This won't work.

     

    But you could copy all the data to a single 16 TB drive temporarily connected to a PC, since you only have 10 TB of data altogether.

     

    Then install 3x16TB + 4x4TB in the NAS (leaving one slot empty), and do a factory install.  Reconfigure the NAS shares and copy the data back.  Then add the last disk to the volume.

     

    Disk I/O for the initial volume build is 32 TB, plus 20 TB of copying, plus 80 TB for the last step.  So about 132 TB altogether.  So it will be faster (though more manual steps) than replacing one disk at a time.

     

    FWIW, if you put a backup plan in place first (as I suggested above), then you could do a factory reset with 4x16TB + 4x4TB in place, reconfigure the NAS, and restore the data from backup.  That would take about 90 TB of disk I/O (not counting creating the backup).

     


    jimk1963 wrote:

     

    https://sabrent.com/products/ec-hd2b

     

    I see that these docking stations perform cloning. So my question is, instead of trudging through resyncs x 4, is it technically feasible to clone each 4TB drive (say, drives 1 through 4) to 4 new 16TB drives, and then simply install the new 16TB drives without any subsequent rebuilding or other “work” on the part of the NAS? 


    Sector by sector cloning would certainly be faster if it works.  32 TB of I/O for the cloning.  The volume expansion would take another 48 TB of I/O when the NAS first boots up (so you aren't avoiding all the rebuilding).  Still, only 80 TB of disk I/O altogether.  You would have to keep the NAS powered down during the entire cloning process

     

    The risk is that the NAS might not expand the volume when you boot it up after cloning. 

    • Sandshark's avatar
      Sandshark
      Sensei

      StephenB wrote:

        You would have to keep the NAS powered down during the entire cloning process

       

      The risk is that the NAS might not expand the volume when you boot it up after cloning. 


      The biggest issue with your proposed "solution" is that the NAS has to stay off during the process.  If it's on and one of the drives is not present, then that removed drive becomes out of sync with the volume and would still need to go through a full re-sync when placed in the NAS, defeating the whole purpose.  While normal expansion does take time, you have access to your data as it occurs.  Here, you don't.

       

      If you did do that, I think the NAS would do the expansion or could be forced to via an SSH command.  If you do a normal one drive at a time expansion, the NAS does not create a partition in the expanded space until it's able to do an expansion, so it's at the same point as your cloned unit would be before it starts the expansion.

      • StephenB's avatar
        StephenB
        Guru

        Sandshark wrote:

        If you did do that, I think the NAS would do the expansion or could be forced to via an SSH command.  


        I agree it should.

         

        I recall one poster saying it didn't in his case, so thought the risk was worth pointing out.

NETGEAR Academy

Boost your skills with the Netgear Academy - Get trained, certified and stay ahead with the latest Netgear technology! 

Join Us!

ProSupport for Business

Comprehensive support plans for maximum network uptime and business peace of mind.

 

Learn More