A few questions and experiences

I have been playing around with Rockstor a lot these last days. This has given me some questions. Some about functionality, and some thats just plain curiosity.

First: What does the three colours (white, blue, orange) that is shown during boot signify? I know its probably a stupid question, but they must mean something besides for having something to look at during boot?

Got my PCIE to mSATA card today (still waiting for the mSATA drive). It works perfectly, and I actually use its SATA port for the boot drive. It has given me the opportunity to work with a setup much like the one I’m planing.

So right now I have 8 disks hooked up to the computer. 6 through the mainboards SATA, one through the SATA port on the mSATA card, and lastly one through an USB adapter.

It all works fine, I now have 7 disks of varying sizes available for the pool.

My plan was to expand the current pool from 4 to 7 disks, and at the same time move from RAID5 to RAID6. But the interface wouldnt allow me to change RAID level. Is this something that will be changed? I know RAID56 is very new to BTRFS (and Rockstor) :smile:

Instead I have just made a RAID5 pool from the seven disks. It worked, and is doing an automatic balancing right now.

I’m rather impressed with BTRFS’s ability to use disks of different sizes, and maintain redundancy.

I guess a cmd line command could be used to change the RAID level?

ECC ram needed? Current RAM is non ECC, how great is the chance of things going wrong, and wouldnt BTRFS’s error correction systems help? Given off-course that the RAM otherwise works OK. The system will primarily be used for media storage, very few really critical data.

Another thing, completely unrelated.

When I use top at the command line to see some info on processes and RAM and so on, it reports an uptime in the upper left hand corner. The web-interface allways shows an uptime off 1 hour more. I think the one “top” is showing is the correct one. Is this a small bug, perhaps caused by daylight savings time?

@KarstenV

Hiya, still reading up about the raid and BTRFS, so can’t give a real good answer, but I think with so many disks, you might want to have a good PSU. You could keep using your RAM as is, I don’t think the investment would justify it, but what you could do is once in a while run MemTest86 to check if your Memory is still fine. A sort of maintenance check :wink:

When RAM is corrupt you can expect bad things to happen.

When booting you can look in your /var/log/boot.log and enter the dmesg command to check what’s going on, hope that helps.

The PSU is an Antec Truepower Trio 430W.

It has got a few years under its belt, but its a Seasonic build, and reviews are favorable. Very good voltage regulation, and good quality components used.
I think it will do the job just fine. I have a watt meter on the wall plug, and it shows 300W max usage, most of the time much lower values. So I’m not that worried on the PSU side of things :slight_smile:

You can change the raid level by clicking on a pool and then clicking resize pool at the bottom. It claims you need to add a drive to change a raid level, which isn’t actually a requirement of btrfs but might be to do it through the gui.

I was trying to change raid level while adding disks, but was told this was not possible.

Its not that much of a problem, but in the end I would like to end up with a RAID6 pool instead of RAID5.

I’m still experimenting, the final build is still some weeks/months away.

Well in that case, at the command line you can run btrfs balance start -draid6 -mraid6 <pool>

@KarstenV, you can rely on command line tools suggested by @seijirou to change your raid profile and Rockstor should pick up changes once the balance is done.

The reason why the UI is extra stringent is that when I rolled out the feature, the device add/remove/balance behaved inconsistently so I put conservative restrictions. Looks like things have improved in btrfs so I can revisit the implementation. The work will be part of #747

I tried the specified cmd, and got this reply:

Unrecognized balance option ‘raid6’

Try this:

btrfs balance start -dconvert=raid6 -mconvert=raid6 /mnt2/<pool_name>

Working, thank you :slight_smile: