RAID 5 system...can I grow it?

[mystykmax]

I just purchased a 3ware 9650SE-4LPML RAID card and am going to use it for my data drives...probably get 3 1TB drives for starters and make a RAID5 system. I have a two-fold question:
1. Can I add another 1TB drive later and make the RAID5 larger?
2. If I had 3 500GB drives and then wanted to migrate to 3 1TB drives, could I replace one drive at a time and when the third one was done, have a larger RAID system?

Thanks in advance...I'm a little new at RAID 5 so be gentle with me!

 

[axan]

1. Yes the card supports OCE so you can grow raid array size, limiting factor is the operating system you use. Certain file systems don't allow partition resize. So even though your array went from 3tb to 4tb your partition would still only be 3tb. If you want to be able to expand the drive size stay away from UFS or ZFS and few others. My personal choice for os would some kind of linux with XFS file system running directly on the block device without any partitions. That makes growing your drive size a snap.

2. Yes but same condition/limitation as 1.

 

[XS Janus]

I have the same controller, but 8port.
You can do it but be aware that it TAKES FOREVER to complete the recalculations.
The speed of the process is around 3-4MiB/s. That means that for a large array it will take weeks to complete. And the hard drives are grinding all the time...

My advice would be to buy all the drives you can fit on the card and forget about expanding.
That's what I did with my 8port card. Didn't want to risk loosing the array just cause I need more space down the road.

 

[ilkhan]

Speed depends on the drives, CPU, and settings.

AND if you end up going 3x1TB, make damn sure you use giant partition tables for the array. Or you wont be able to grow without wiping everything. (Im facing that right now)

 

[Blue Fox]

Speed depends on the drives, CPU, and settings.

AND if you end up going 3x1TB, make damn sure you use giant partition tables for the array. Or you wont be able to grow without wiping everything. (Im facing that right now)

You can use 4k blocks instead of 512b. That lets you go to 16TB instead of 2TB.

 

[unhappy_mage]

If you want to be able to expand the drive size stay away from UFS or ZFS and few others.

To clarify this a bit, if you have a ZFS pool on a RAID 5 array that you expand, you'd have to either export and re-import the pool to get it to work or reboot. But after that it would detect the larger size and transparently use all of it. The "problem" comes in when you use ZFS' software raidz; it doesn't have restriping capabilities, so you can't add another device to that vdev.

That said, there aren't any device drivers for 3ware cards in Solaris. You could run into this in *BSD, I guess.

 

[mystykmax]

will I get a virtual kick in the nuts for using Vista x64?

My intent for this is that I'll be using it for storing pictures and video and sharing the files on my home network. The machine I'm using is a Q6600@3.2 with 8GB ram. Basically I would just be putting "My Documents" (well, vista calls it just "Documents") on that drive so when I upgrade a system I can just keep things in one spot. Sounds like maybe I should just get 3x1TB (or maybe 4?) and when it's time to upgrade, just buy new drives and suck it up and transfer everything? This is more complicated than I though if it will take weeks to resize things. Thanks for the help so far, folks, I appreciate it.

 

[ilkhan]

will I get a virtual kick in the nuts for using Vista x64?

My intent for this is that I'll be using it for storing pictures and video and sharing the files on my home network. The machine I'm using is a Q6600@3.2 with 8GB ram. Basically I would just be putting "My Documents" (well, vista calls it just "Documents") on that drive so when I upgrade a system I can just keep things in one spot. Sounds like maybe I should just get 3x1TB (or maybe 4?) and when it's time to upgrade, just buy new drives and suck it up and transfer everything? This is more complicated than I though if it will take weeks to resize things. Thanks for the help so far, folks, I appreciate it.

yes. A lot less of a kick with win server though
doesnt usually take weeks. a few days perhaps, but weeks would be lowest priority, using the drive, on a 6 or 7 card array. And you have to expect it to take a while under those circumstances.

Im still not sure what you want? Just a seperate system for your data to be stored on? Sounds a bit overkill hardware wise (quad) for that.

 

[axan]

vista x64 will work but make sure you use gpt partition tables, not mbr. Only vista business and ultimate support that.