Questions about build and expand

Hi All,

For a video storage server i need to build a system.
I love centos and prefer rockstore before freenas ;). Also the features into rockstore a really nice.

I need 80TB storage, and want to build in some safety with raid6. It will be a growing storage till 80TB and i will start with 4x 6TB disks ( to keep the start cost low ) into the system and want to build it up to 16x 6TB.

Now my question, is it possible with rockstor to add every time more disks to let grow my storage without losing any data.

System setup.

16x hotswap supermicro case
Supermicro X10SLL-F
Intel Xeon E3-1220 V3
16Gb ECC Memory
LSI MegaRAID SAS 9260-16i
4x 6TB Disks

Thanks a lot for your feedback.


@oxzhor First off welcome to the Rockstor community.

Others here are more qualified to comment on your hardware questions but I can say that the parity raid levels of btrfs ie raid5/6 are not considered production ready so they are not really an option for your here. Even more so at the size of storage you are planning on. Please see the following forum thread for more info on this:

That is certainly the hope, given the raid5/6 caveat. Of course there is never a guarantee but btrfs 1 and 10 are your only choices here. This all assumes you are to use the raid controller in HBA JBOD’s mode. Again there are others far more knowledgeable in the forum so hopefully you will gain some more feedback in time.

Please also see the Pool resizing section of the official Rockstor docs.

I know there are others here who also use Rockstor with LSI controllers but not sure if that exact model is represented.

Hope that helps.

Hi Phill,

Thank you for your quick reply.

JBOD cads are the lsi 9240-8i, lsi 9201-16i, HighPoint Rocket 750 etc…

Like you say it is never secure enough, but i want to keep the risk small as possible. With raid 10 i lost to much diskspace so that is no option raid5/6 is not yet good supported so that is also not a option for me.

I think a good solution will be to work with offside backupstorage connected via 10G and sync this with the main storage.

Hi Remco

You could have a lok at this site, it has some good articles about raid solutions for different usages.


Sorry buddy, but in terms of RAID6 you are out of luck with BTRFS … right now raid5 & raid6 status is “it will eat your data”. I know that there are people that use it and they have no problem for time being … but a lot of them then pop up on btrfs mailing list with “please help me rescue my production raid 5 setup” :slight_smile:

Right now problems that exist with RAID 5 & 6 on btrfs:

  • write hole - you loose power mid write (data or metadata) = your data goes bye bye
  • scrub issues - yes … it’s supposed to work, a lot of people come back with random errors on that
  • parity checksum does not exist - if you data goes bad, you have no idea whenever parity is OK / not OK … so you might be rescuing from garbage parity
  • removing a disk with bad sectors can get you stuck … and since there is a write hole + no crc on parity you want gracefully remove disk rather than just unplug it and say “hey btrfs, disk is gone, deal with it”

I know, this sucks and sucks hard … I personally run raid10 for lack of any other option :confused:

Now, this will sound strange - but how much do you care about that data on your video storage server ? Is that a back up (raid10) ? or a hyperfast access where you rotate your data very quickly … because your workstation does not have enough storage locally for storing all data in your projects (raid0 OR raid5/6) ? I know that this is strange but I’ve seen weird solutions for video editing … for even video conversion when you drop video from DVCPRO into SDI stream and then convert it to ASI …

Of course you could go ZFS … but that one requires you to use same size disks … shrinking ZFS is “fun” … your 16GB ram would be cannibalised by zfs driver …