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ntsc · Jul 11, 2007, 10:58 AM

I wonder if anyone has any experience with Volume Management software for OS X. Is there any to begin with? AFAIK Apple doesn't provide any but I was wondering if there were any implementations, perhaps included with OS X server or as part of Apple's SAN offering or even as third party software.

I'm looking for something the abilities of the likes of Solaris Volume Manager (SVM) or Veritas's volume management software. Perhaps the lack of software like this is part of the reason Apple is so interested in getting ZFS in OS X?

If anyone has any thoughts on this I'd be pleased hear them.

larkost · Jul 11, 2007, 04:27 PM

What is your goal here? Apple's typical approach when you need volume management is to go external and use things like XSan to do that management.

Short of that Apple handles multiple (separate) volumes just fine, has a middling soft-RAID solution, and has some great image tools to help you with migrations. But you have indicated a huge space without any details.

CatOne · Jul 11, 2007, 11:43 PM

Not sure exactly what you're looking for. There are a number of "volume management" solutions but without word on what you really want (SAN?) it's tough to recommend anything.

ntsc · Jul 12, 2007, 05:25 PM

Sorry, I suppose i should have been more specific. What I'm interested in achieving is mirroring the boot partitions. For example in a previous setup with, admittedly much higher end, Sun equipment I used 3 internal disks to create a three way mirror of the boot disk. The aim was to create a highly available system. In SVM one can do this by mapping each partition required for boot to a 'meta-device' and then setting them up as mirrors of each other which means that they are visible as a single 'meta-device' which is then set as the boot device for the system. I'm not trying to replace mid-range Sun equipment with Apple's but I just wondered how close I could get using MacOS.

I suppose Apple's answer to this is really their RAID implementation which i think one can boot from, right? Is there anything perhaps as a little closer to SVM perhaps with mirrors sometimes its nicer just to have mirrors rather than having to wait for something rebuild a RAID mirror.

ntsc · Jul 12, 2007, 05:26 PM

Oh also, does anyone know if I could boot from Apple's SAN unit? Just some idle wondering....

OreoCookie · Jul 12, 2007, 06:34 PM

First of all, your questions does not pertain to `volume management' (which is something else), but just about RAIDs on OS X. Of course you can boot of RAID1 and RAID0 volumes on OS X, that just works out of the box. If you want to go for a more professional solution, you should go for a hardware RAID anyway. This is then completely transparent for OS X.

Volume management is about pooling space across several servers for instance, `RAIDing RAIDs' so to speak.

CatOne · Jul 13, 2007, 07:57 PM

Originally Posted by OreoCookie

First of all, your questions does not pertain to `volume management' (which is something else), but just about RAIDs on OS X. Of course you can boot of RAID1 and RAID0 volumes on OS X, that just works out of the box. If you want to go for a more professional solution, you should go for a hardware RAID anyway. This is then completely transparent for OS X.

Volume management is about pooling space across several servers for instance, `RAIDing RAIDs' so to speak.

Xsan wouldn't be a good fit here. You can't boot off it, and it's very complex for anything under 3 or more workstations which want to share the same large pool of storage.

I can't recall if you can boot Intel machines off the Xserve RAID. Something tells me there was an issue initially; I can't recall whether it was resolved.

Anyway, "volume management" is built into the OS. You can create a RAID using Disk Utility, either via the GUI (in /Applications/Utilities), or via the command line (see 'man diskutil' for details). The built in software can do RAID 0 and RAID 1. There is also a 3rd party product called SoftRAID which has a few more features and a rock solid reputation.

ntsc · Jul 15, 2007, 05:27 AM

Ah of course, thanks guys! I'd forgotten about using the RAID software for mirroring, I guess I just spent a little too long working with Solaris for this stuff

The XSan thing was more idle musing than anything else, if only my budget would stretch to something as nice!

Oreo, I would actually respectfully disagree with your definition that this isn't volume management. Although I'm not trying to pool the storage together I was looking to create and manage a volume which surely qualifies as volume management?

Anyways, I like the idea of RAID0 for booting from, obviously the idea is that the system can survive a boot disk failure without having to rebuild the system.