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Waragainstsleep · Jun 11, 2011, 04:07 PM

Anyone here have much experience using iSCSI RAID kit with Snow Leopard/Server?

How do you find it?
How does it compare to 'real' SCSI? (UW160 or 320)

Is it straightforward to set up? Does SL have built in initiator support or do you use 3rd party?

seanc · Jun 11, 2011, 06:19 PM

I've used iSCSI to connect to NAS boxes that run RAID5 arrays... is this what you mean?

Waragainstsleep · Jun 11, 2011, 08:42 PM

Yes, absolutely. I've only ever used UW SCSI and Fibre channel. How does iSCSI stack up? Looking to replace an ageing Xserve RAID without paying the premium for a fibre rack unit.

seanc · Jun 11, 2011, 08:54 PM

Well obviously it only works at network speeds and so far I've only used it with Windows.
I'll let you know about OS X on Monday.

Waragainstsleep · Jun 12, 2011, 05:48 AM

Ta very much.

What sort of RAID boxes have you been using it with?

seanc · Jun 12, 2011, 06:50 AM

FreeNAS - which is whatever hardware you feel like using and we have one Buffalo Terastation iSCSI unit at a customer site.

besson3c · Jun 12, 2011, 10:26 AM

The closest I've come is ISCSI and ZFS in Solaris 10, sorry...

Cold Warrior · Jun 12, 2011, 10:34 AM

Seanc,
How is freenas compared to a software raid 0 (e.g., Win server 2003)? Running the latter at the moment, great speeds, but I have freeness sitting on my desk and have been considering it.

besson3c · 11:07 AM

Originally Posted by Cold Warrior

Seanc,
How is freenas compared to a software raid 0 (e.g., Win server 2003)? Running the latter at the moment, great speeds, but I have freeness sitting on my desk and have been considering it.

I don't think FreeNAS cares about what hardware you throw at it, it just allows you to setup shares and stuff. I.e. its performance depends on the underlying hardware.

Cold Warrior · Jun 12, 2011, 10:42 AM

Yes, but in a software raid, hardware being equal, maybe freenas is faster than win 2003.

seanc · Jun 12, 2011, 11:03 AM

I've not tried RAID0 and I probably never will. I'll take the safety of my data over speed any day.

besson3c · Jun 12, 2011, 11:09 AM

Originally Posted by Cold Warrior

Yes, but in a software raid, hardware being equal, maybe freenas is faster than win 2003.

Oh, I see what you mean... Maybe the question is actually whether ZFS or UFS (depending on how you'd intend to use FreeNAS) is faster than NTFS?

Cold Warrior · Jun 12, 2011, 11:13 AM

That and possible OS differences (overhead, etc.). But I may start a new topic because I don't want to distract from the op's concerns.

Waragainstsleep · Jun 12, 2011, 02:30 PM

I'm just looking for a cost effective rack mounted RAID solution. Needs to be 8TB with room to grow ideally. Its going to be managed by an Xserve so I don't need any fancy sharing features or a NAS, I just want a straight up replacement for the Xserve RAID.

Trouble is fibre channel based RAIDs are extremely expensive and I'm inclined to think that regular SCSI is getting a little bit old fashioned these days so I thought I'd look into iSCSI. I never even realised until recently it could be done over ethernet, I had thought it was a newer SCSI variant. I was wondering if Apple had built it into Snow Leopard but it looks like you have to get the open source initiator from Studio Network Solutions.

chris83179 · Jun 16, 2011, 12:26 AM

ATTO has an iSCSI initiator but costs $$. GlobalSAN is your only other free option that I have found. I've setup several iSCSI Infortrend chassis with OS X and GlobalSAN. User/Target authentication can get tricky, depending on the chassis.

Performance seems to be pretty good with iSCSI. I was able to transfer files faster on an iSCSI mounted volume over gigabit, vs a network share which is hosted on a fibre channel raid...

Haven't used iSCSI in a live environment though, only for offsite backups...

Waragainstsleep · Jun 16, 2011, 12:28 PM

Originally Posted by chris83179

ATTO has an iSCSI initiator but costs $$. GlobalSAN is your only other free option that I have found. I've setup several iSCSI Infortrend chassis with OS X and GlobalSAN. User/Target authentication can get tricky, depending on the chassis.

Performance seems to be pretty good with iSCSI. I was able to transfer files faster on an iSCSI mounted volume over gigabit, vs a network share which is hosted on a fibre channel raid...

Haven't used iSCSI in a live environment though, only for offsite backups...

This sounds very promising. I have specced up a nice Promise system with 16TB in it. Now trying to decide if I'm brave enough to try XSAN over iSCSI....

Many thanks guys!