I'm unclear as to if it is possible to add an expansion chassis (EDA4000) to my 4312x system and grow the RAID storage capacity with XRAID currently configured? My 4312x system has 12 - 6TB drives and I'm wanting to add the EDA4000 with 10TB drives. It appears that I cannot do that under XRAID using the EDA4000 exp. chasis under XRAID? I wasn't able to find any documentation as to the specifics of this. Thanks

Hi dallis11 Welcome to the Community! XRAID is not supported across different chassis. Also, it is not recommended since in the event that the external chassis gets disconnected or fails to operate all disks will appear as dead, You should have at least 2 volumes when using an external chassis. One with the NAS and the other from the EDA4000. Hope this helps! Regards

I had read that X-RAID is not supported across chassis.. If converted to Flex-RAID is it possible to extend across chassis? Data cannot be across multiple volumes? What I want to do essentially is grow my storage capacity utilizing the expansion chassis using my current dataset. I don't quite get conceptually if the same data can exist in multiple volumes? What would be the best approach to do this? I was thinking that vertical expansion using the 4312x would be the least invasive approach in that theoretically there would be no downtime? The issue is that I'm at 80% now. Thanks!

A volume is basically a virtual disk. Users don't see volumes, what they see is a list of network shares. That means that the volume structure is immaterial to them. So the process here is switch to flexraid create a second volume on the EDA4000 create some shares on that volume. These can be new shares, or you can move some shares to the EDA4000 from the existing volume on the 4312 To move shares from the RN4312 you create a share on the EDA4000 with a temporary name set up an rsync backup job on the NAS to copy an existing share ot the new one delete the original share rename the EDA4000 share to the match the name of the original share. Note you can't move the "home" shares for your users - they have to stay on the original volume.

Hi dallis11 You are correct that data cannot exist coherently on two different volumes. It also means that the two different volumes would be separate entities, holding separate data. I understand your desire to expand the raid as that is obviously the easiest answer. You keep one volume and it just gets bigger. Easy management. In theory you can expand the volume across to an EDA with Flex-RAID (or at least you used to be able to). However, this is just a very bad idea altogether. Problems with having one raid volume across main NAS and EDA is single point of failure. Your EDA is connected via eSATA or similar and if that connection went bad or the EDA went bad, your entire volume will go down with it. Secondly, performance would be poor because instead of each disk having their own SATA connection to the main board, now all disks in the EDA must share the connection over the main chassis... and since all disks in the entire raid are depended on each other, performance across the board will suffer. It is just not recommended in any scenario. Making a separate volume in the EDA is the way to go. Yes, you have to manage two volumes but that is how it is. One volume could be your archive data for example. You problem is understandable and a big issue in IT today. The need to (endlessly) expand but not have multiple volumes. It is a very hard problem to solve and also why the real big guys in storage (EMC, NetApp, etc.) charge insane money. Their solutions are super scalable but unless you are very big company the cost will be a massive hit. On the ReadyNAS (and other similar products) there is not much you can do but restructure the data layout and simply deal with multiple volumes and data separation. I hope that makes sense. Cheers

First and foremost.. thanks for the information.. Let me ask you this: So, my users are all Linux based and use Linux workstations and write data solely to these homes that were created. As such, they all have home directories which I had created under a /data area. We didn't use the built in "homes" provided. In this scenario would I be able to migrate these directories to the EDA? Would the performance be reasonable over the SAS connection with the 4312 to EDA? I was thinking that if I went this route I could use 10 to 12 TB drives x 24 to account for future needs. I made the mistake of going only 6TB drives in the 4312 x 12 which they have outgrown quickly. They are computational research scientists and generate lots of data. I'm still wondering if a good approach would be to just stary with XRAID2 on the 4312 and upgrade the 6TB drives to say 10TB drives x 8 drives initially due to rebuild time? Thanks!

4312 add EDA4000 Expansion Chassis / RAID Expansion

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Marc_V
NETGEAR Employee Retired
Mar 26, 2019
Hi dallis11

Welcome to the Community!

XRAID is not supported across different chassis. Also, it is not recommended since in the event that the external chassis gets disconnected or fails to operate all disks will appear as dead,

You should have at least 2 volumes when using an external chassis. One with the NAS and the other from the EDA4000.

Hope this helps!

Regards
- dallis11
  Aspirant
  Mar 26, 2019
  I had read that X-RAID is not supported across chassis.. If converted to Flex-RAID is it possible to extend across chassis? Data cannot be across multiple volumes? What I want to do essentially is grow my storage capacity utilizing the expansion chassis using my current dataset. I don't quite get conceptually if the same data can exist in multiple volumes? What would be the best approach to do this? I was thinking that vertical expansion using the 4312x would be the least invasive approach in that theoretically there would be no downtime? The issue is that I'm at 80% now. Thanks!
  - StephenB
    Guru - Experienced User
    Mar 26, 2019
    A volume is basically a virtual disk. Users don't see volumes, what they see is a list of network shares. That means that the volume structure is immaterial to them.
    
    So the process here is
    
    switch to flexraid
    
    create a second volume on the EDA4000
    
    create some shares on that volume. These can be new shares, or you can move some shares to the EDA4000 from the existing volume on the 4312
    
    To move shares from the RN4312 you
    
    create a share on the EDA4000 with a temporary name
    
    set up an rsync backup job on the NAS to copy an existing share ot the new one
    
    delete the original share
    
    rename the EDA4000 share to the match the name of the original share.
    
    Note you can't move the "home" shares for your users - they have to stay on the original volume.