Adding extra HDD

[Srikanth K Kota]

Hi there,

Background:
I was loosing lot of data as I was copying data to external disks and not maintaining them properly. So initially I bought a Seagate NAS and it was burnt out in a week due to the heat it is generating. After few interactions with them I realized that was a mistake. Finally my search has showed that FreeNAS is the best option and I have decided to built one. Bought a Dell Workstation, ECC Ram, SSD HDDs for OS and Jails, one 3TB HDD for the storage, SAS/SATA PCIe card. At this point, I couldn't afford to buy more HDDs.

Current State:
After some research finally I could able to setup the NAS with Plex Media Server and it is working fine. I am planning to add 5 more disks in future one after the other in the coming 3 - 4 months.

Problem Statement:
This month I am planning to buy one HDD and create a mirror for the existing disk. How should I do it? When I have all the 6 disks, then how can I create a RaidZ2 with all these disks and the most important thing is that I do not want to redo the whole stuff from scratch. I should be able to add the disks to the current setup.

Please help me either by giving the instructions or pointing me to the right article on how to do it. In case any point is not clear, I will give more details so the situation is very clear.

 

[danb35]

how can I create a RaidZ2 with all these disks and the most important thing is that I do not want to redo the whole stuff from scratch.

Not possible. It's possible to add a second disk as a mirror of a first (though unfortunately not through the GUI), but it's not possible to convert either a single disk or a two-disk mirror into a RAIDZ2 pool with additional disks. You'd need to back up your data, destroy the pool, create a new RAIDZ2 pool with the desired disks, and restore.

 

[garm]

If you don’t want to buy 6 drives on an single paycheck then just buy them as you go and add them to your pool in mirror vdevs. That is what I do for expansion. No need to clock lifetime hours on empty drives, I just expand as I go.

 

[Srikanth K Kota]

Thanks a lot for the confirmation danb35. Now one quick clarification I need is how many number of Hard disks do I need at minimum to create RaidZ2.

 

[Srikanth K Kota]

If you don’t want to buy 6 drives on an single paycheck then just buy them as you go and add them to your pool in mirror vdevs. That is what I do for expansion. No need to clock lifetime hours on empty drives, I just expand as I go.

Thanks garm for your kind reply. Could you please guide that process or point me to the detailed post so I can give a try?

 

[danb35]

Now one quick clarification I need is how many number of Hard disks do I need at minimum to create RaidZ2.

The minimum is four disks, but you can't add disks to the RAIDZ2 once it's created. So if you create it with four disks, you can't later change it to a six-disk RAIDZ2 without doing the backup/destroy/recreate/restore thing again.

 

[Srikanth K Kota]

The minimum is four disks, but you can't add disks to the RAIDZ2 once it's created. So if you create it with four disks, you can't later change it to a six-disk RAIDZ2 without doing the backup/destroy/recreate/restore thing again.

Ohhh Okay! Thanks a lot for mentioning that to me so I don't do that mistake.

 

[Inxsible]

@Srikanth K Kota you should probably read up on the basics of FreeNAS and ZFS and how they work. That should give you a head start.

Like @danb35 mentioned, you cannot change an existing RAID configuration. What you can do however, is keep adding vdevs to the same pool to increase the number of drives and usable storage space.

You should also look into mirrors instead of RAIDZ and figure out if that helps you out more in your current situation. I started using FreeNAS on 2 drives (500GB and 1TB) as a mirror until I was sure that I was going to keep FreeNAS as my storage solution. Then I replaced those drives with bigger HDDs. Once I had used up about 60-70% of the drives, I added 2 more drives as a mirrored vdev to increase my storage space. Mirrors allow you to buy 2 drives at a time instead of 4 or 6 etc in RAIDZ2 configuration.

 

[Srikanth K Kota]

@Srikanth K Kota you should probably read up on the basics of FreeNAS and ZFS and how they work. That should give you a head start.

Like @danb35 mentioned, you cannot change an existing RAID configuration. What you can do however, is keep adding vdevs to the same pool to increase the number of drives and usable storage space.

You should also look into mirrors instead of RAIDZ and figure out if that helps you out more in your current situation. I started using FreeNAS on 2 drives (500GB and 1TB) as a mirror until I was sure that I was going to keep FreeNAS as my storage solution. Then I replaced those drives with bigger HDDs. Once I had used up about 60-70% of the drives, I added 2 more drives as a mirrored vdev to increase my storage space. Mirrors allow you to buy 2 drives at a time instead of 4 or 6 etc in RAIDZ2 configuration.

I sincerely appreciate your suggestions Inxsible! Could you please point me to a right blog where I want to read and understand more? Also as per the previous suggestions, I will not be able to do mirror from GUI. So will I able to achieve it without destroying and recreating?

 

[garm]

http://doc.freenas.org/11/zfsprimer.html#zfs-primer
http://www.manpagez.com/man/8/zpool/
http://www.manpagez.com/man/8/zfs/

 

[MrToddsFriends]

Also as per the previous suggestions, I will not be able to do mirror from GUI. So will I able to achieve it without destroying and recreating?

Retroactive conversion of a single disk vdev into a mirror vdev using the CLI:
https://forums.freenas.org/index.ph...or-by-adding-a-drive.14880/page-3#post-399369

Also be sure to read cyberjock's slideshow for general information about ZFS.

 

[wblock]

http://www.manpagez.com/man/8/zpool/

I'd suggest using FreeBSD.org for the man pages. Not only are they more likely to be correct, they have better formatting. The main interface is at https://www.freebsd.org/cgi/man.cgi. The search URL really only needs ?query=zpool added to it:
https://www.freebsd.org/cgi/man.cgi?query=zpool
https://www.freebsd.org/cgi/man.cgi?query=zfs

 

[garm]

Ya sure, ordinarily I would but they never loaded on the phone so I googled :)