Expand Software RAID-5 Server 2008 R2

[CPressland]

Right - Well I just basically spent two days reading up on unRAID solidly, I've purchased it and am currently preclearing my disks with the script prior to getting the array back online. Should be done in 6 hours but I'll be asleep by then, so I'll migrate the Data back to the Server tomorrow.

Setup will be:

250GB /dev/hdb - Data

2000GB /dev/sdb - Data

2000GB /dev/sdc - Data

2000GB /dev/sdd - Data

2000GB /dev/sde - Parity

My understanding is I'll need to upgrade the Parity Drive before I can expand those other disks beyond 2TB, so I'll need a way of identifying that drive in the MicroServer, or I'll just boot a LiveCD on a USB and find which drive has a bizzarre FileSystem on it.

Next upgrade will be 4000GB drives, but that won't be till mid-next year.

[+BudMan MVC]

So you going to run it vm with rdm, or going to use the whole thing as just unraid?

Yeah your parity drive has to be as large as your largest data disk. So if you want to go with bigger than 2TB data, then you will need to update your parity to 2.5 or 3, etc.

[CPressland]

I have converted 'Galactica' the 8TB Server to run unRAID. Eventually I'll run 5x4TB on it. Just wish I'd moved the parity drive to the HDB slot...

[CPressland]

Looks like External USB Hard Drives can be added to the Array also, interesting, but I think I'll have the Server share them as separate, non-redundant, drives.

Maybe for backups of the N40L... hmm..

[+BudMan MVC]

If you going to do that you might want to look at the snap addon

http://lime-technology.com/wiki/index.php/UnRAID_Add_Ons#SNAP

[CPressland]

I'm going to look at Addons as soon as I'm using a Final Release and not an RC

[mrp04]

I'm currently trying out FlexRAID for my data protection needs. Irreplaceable files are on 3 computers at 2 different locations. My media files are all stored on my desktop and I just installed FlexRAID and installed another 3TB drive to be used as parity.

You only need one parity drive as large as the biggest drive to be protected. That way if any one drive dies, I can replace it and recover. The only issue is when multiple drives die. That will result in data loss, but the files aren't important and can be replaced if needed. Since it's not real RAID, only the data on the dead drives is lost. If the parity drive and one other drive die at the same time, I only lose one drive's worth of data. If two data drives die, then both are lost and the parity data is useless.

I find that one $120 drive is a great balance point between safety and cost effectiveness. The odds of two drives dying at the same time is pretty low and the data is replaceable, so it's a risk I'm willing to take.

[CPressland]

Just one thing to note, when running iPerf to the new unRAID Server I'm seeing approx 120MB/s speeds over the network, so it's maxing out Gigabit easily!

When writing to the array, i'm maxing out at 10MB/s with it occasionally jumping to 40MB/s for a few seconds...

Any ideas?

[+BudMan MVC]

You need a cache drive ;) This is known issue with unraid that writing is slow.. So a cache drive allows you to get full write speed to one spindle while it then moves the files to your parity array after.

In your one setup I would prob make your 250GB drive a cache drive.

[CPressland]

No can do now - I cannot bring the array back down and swap a drive out as a Cache instead of a Data Drive :(

[CPressland]

Managed to reconfigure as a Cache Drive with some tips from the forums, now I'm writing at 15MB/s, wasn't really worth it for a 5MB/s improvement.

[CPressland]

Right, so the cache drive actually isn't enabled by default, you have to manually enable it on user shares! wow, this thing is really taking me some getting used to! lol

[theefool]

Interesting I was wondering what kind of I/O hit unraid would have. Also, are those 5400 or 7200 rpm drives? Would having a 10k or ssd for caching be better?

[CPressland]

Interesting I was wondering what kind of I/O hit unraid would have. Also, are those 5400 or 7200 rpm drives? Would having a 10k or ssd for caching be better?

I was just thinking the same thing, but I cannot justify the cost of upgrading the cache drive right now. All drives are 7200rpm. a 256GB SSD would be great for a cache drive, but thats just too expensive right now.

[+BudMan MVC]

Well to me write speed is not all that important if your using it to serve up your media from, read is what matters it serving up your HD media. If you moving lots of data at once sure than a 250GB SSD might be in order, but something like even 32 or 64 would be very useful into just getting your new files there and then forgetting about them as they get moved over to the parity array.

[CPressland]

Well, I'm slowly learning my way around this OS, and the Cache drive is helping to a degree, but only being able to add 250GB of Data at a time is becoming a pain. But then it's not every day I'll be migrating ~2TB over to this server.

[CPressland]

Ended up installing a custom BIOS to enable AHCI on the other ports on the server, ended up improving AFP speeds from 10MB/s to 25MB/s.

That said AFP is crazy unstable on 5.0rc4

[+BudMan MVC]

"to enable AHCI on the other ports on the server"

Didn't we talk about this before?? Thought you had the current bios that allowed this, or wait this is your N36L, you also have a N40L as well? So this is older model that did not have the current bios or bios hack. Did they not enable it in the standard bios like they did for the N40L?

[jasondefaoite]

Did they not enable it in the standard bios like they did for the N40L?

No, the N36L needs a patched/hacked BIOS to enable that, and after flashing it is still disabled. You need to go in and enable it.

Budman, any thoughts on Storage Spaces with Windows 8? Have you played around with it? I'm thinking of wiping my WHS2011 install on the N36L and going with win8. The main use of the server was as a NAS.

[TurboTuna]

Nice to see you've finally gone over to unRaid! If you've got any questions I'm happy to give it a bash.

Bare in mind if you're using your cache drive the data isn't moved off of that drive until around 3am. So while on there it isn't backed up or protected.

I don't have this issue as I don't have unRaid running with a Parity drive.

[+BudMan MVC]

No I have not played with w8 spaces as of yet, I have fired up a couple of the beta's - and to be honest the UI was so off putting I have not bothered to dig much deeper. Because I can tell you this for sure, if there is no way to use the standard desktop - your not going to see many companies move to this version any time soon.

Most enterprises don't move their users until sp1 of new OS anyway, sure you will have a few beta testers in IT dept, etc. But not a major move - you would not believe the issues users have with just the simple office ribbon when that changed. Changing the UI, yeah companies are not going to like that at all! So got plenty of time to get up to speed with it. Not like its going to be mainstream for months and months, if not years after it releases.

**** lots of companies are still on XP ;)

As to " I don't have unRaid running with a Parity drive. " What?? You meant "cache" drive right - I don't think its possible to run unraid without the parity drive?? If so please point this out!