RAID - What I need and how to go about it

[inigel]

This is probably the bazillionth thread on RAID setups and whatever, but I have a 2008 Octo Mac Pro and I want to set up a RAID 1 with my hard drives.

I hope experienced users can help me out with some questions.

1) I know I'm going to need to get a RAID card, are they any good (preferably cheaper) equivalent cards compared to the Apple RAID card?

2) Is it advisable to get two identical hard drives, (brand, model etc.) or is it fine to just use the same capacities?

3) If one hard drive fails, is there an indicator that a drive has failed?

4) Finally, if a drive does fail, how can I go with a restore or replacing the faulty drive?

Any help would be greatly appreciated, and 100 internets to anyone with some really helpful information!

 

[costabunny]

http://guides.macrumors.com/Mac_Pro_Hardware_resource is a good friend for you

Basically for a reliable RAID system a Hardware card is better than using MAC OS X built in software raid.

Getting two identical drives is always preferable (down to the level of firmware on them) - some argue that if a batch has an issue this is a bad thing. Youll have to decide (I have four identical Seagate 'cuda's in mine).

In a mirrored system yes either the RID HW or the OS will let you know it is running in degraded mode (drive failure) and needs attention. With most setup's it is simply a matter of replacing the failed unit and then the raid volume will repair itself (the hardware option will rule supreme here as it will not lag your system noticably when rebuilding a mirror).

You can use SW for the mirror, thus enabling you to still use a third drive for bootcamp (the Apple card ont run bootcamp but you can get a sas cable and run it off the original motherboard with a HDD in the second optical bay).

The Caldigit card (I beleive) needs prepping before you can install OSX on it (I read that somewhere). Personally I like and use the Apple RAID.

 

[valdore]

Pardon me if I'm spreading misinformation with this, but I thought I heard that Snow Leopard 10.6 will somehow make hardware RAID obsolete?

 

[costabunny]

Pardon me if I'm spreading misinformation with this, but I thought I heard that Snow Leopard 10.6 will somehow make hardware RAID obsolete?

Oooh does it download a RAID card?? (sorry for the sarcasm)

No HW vs SW RAID will always be here. I think you are referring to the possible use of zfs file system in Snow Leopard. This is a new way to manage storage space, but it still needs physical disks n so forth. A Hardware RAID will work and so will a sw (but also the filesystem itself does some RAID stuff).

 

[inigel]

You can use SW for the mirror, thus enabling you to still use a third drive for bootcamp (the Apple card ont run bootcamp but you can get a sas cable and run it off the original motherboard with a HDD in the second optical bay).

That's a bummer about the Boot Camp, I only use Windows for games though, I guess I can build a new box for that.

One Hundred Internets for you!

EDIT: The 2nd optical bay is off limits, I have a secondary burner there

 

[costabunny]

A reasonably cheap alternative (for the bootcamp paradox) is to get a PCIe SATA card with an external eSATA enclosure - this will be seen as any other hard disk and thus is bootable for bootcamp and/or mac.

 

[Virtuoso]

The hardware RAIDs are good if you want to run a RAID5/6/10 etc as they can handle the more complex RAID configurations without any performance penalty on your main CPUs. They are also useful if you want to run a RAID with more than 4 drives (the Caldigit allows for RAID arrays of 16 drives) or if you want to use the fast but expensive SAS drives.

If you just want to run a RAID1 with 2 hard drives, a $500 hardware card might be overkill, and may be more trouble than it's worth. If you stick to a software RAID, you could have one boot drive, 2 data drives in RAID 1 and the 4th drive set aside for Bootcamp.

Another thing to consider - if it's just for data protection, is RAID1 going to do anything for you that you couldn't do using Time Machine with a dedicated internal drive? Just a thought...

 

[heppy]

I haven't got one yet but I hear really good things about the Drobo unit

 

[Pressure]

Pardon me if I'm spreading misinformation with this, but I thought I heard that Snow Leopard 10.6 will somehow make hardware RAID obsolete?

I guess you are thinking about the new filesystem (ZFS) that is currently only supported under Mac OS X Server

ZFS enables dynamic striping that makes it easy to add drives to the pool and it automatically balances the write load across them.

 

[Umbongo]

I haven't got one yet but I hear really good things about the Drobo unit

A Drobo is fine for storage, but not something you'd really want to work from directly and if it fails you need another Drobo unit if you want to get your data off the disks. It is an alternative though for a lot of people.

 

[wheezy]

I am currently running a SW RAID1 in my MP and am perfectly happy with it; mainly I wanted redundancy on my photos

1 - 320GB OS, etc
2 - 500 Time Machine
3&4 - 1TB RAID 1 for Photos

I'm using Samsung F1 drives in the RAID and they're pretty quick, much faster than the Seagate 320 that my system came with. I'm not a hardware spec geek but I know I can write to that drive awfully fast. (Mind you, I'm coming from a MacBook 5400rpm drive and a Firewire 400 External)

 

[Virtuoso]

I haven't got one yet but I hear really good things about the Drobo unit

The marketing is good, but it's a different story on the user forums. Loads of issues and they are VERY slow. Even with 4 drives, the new firewire 800 model only manages about 16MB/s which is shocking.

 

[inigel]

Another thing to consider - if it's just for data protection, is RAID1 going to do anything for you that you couldn't do using Time Machine with a dedicated internal drive? Just a thought...

I prefer the idea of having an exact mirror of my files. Plus I tried a Time Capsule and it filled up too quickly with temp files.

 

[nanofrog]

I prefer the idea of having an exact mirror of my files. Plus I tried a Time Capsule and it filled up too quickly with temp files.

Am I correct in assuming you just want a 2 drive RAID 1 then?

If so, and you only intend to use it under OS X, software RAID would suit your needs, and is less expensive I should think.

However, if you do want to run it under windows as well, you would have to use a hardware solution. You might want to take a look at Accusys, as they are the OEM for CalDigit, and less expensive. They make a 4 port card for $270, available at newegg.com. Note, that it supports SATA only, as does the CalDigit, and works under OS X & windows.

 

[Alrescha]

The marketing is good, but it's a different story on the user forums. Loads of issues and they are VERY slow. Even with 4 drives, the new firewire 800 model only manages about 16MB/s which is shocking.

Not just shocking, but not entirely true. I can get about 24 MB/s with mine using Firewire 400.

A.

 

[Catch]

A Drobo is fine for storage, but not something you'd really want to work from directly and if it fails you need another Drobo unit if you want to get your data off the disks. It is an alternative though for a lot of people.

In my business we use Drobos for simple backups and they work extremely well. I use one at home as well and its amazing...

Other 'pro' raid solutions come at a very high price but obviously provide allot more 'robust' features for 'pros'...

Raids can become very complex and expensive very fast if you want more than 'prosumer' performance...

C

 

[offshoresa65s]

Hi

I live in Australia also and I invested in a Firmtek 5 Bay encolsure and a HighPoint Rocket Raid 2314 PCIe card for my early '08 MacPro.

I think the best reading in establishing a RAID system is to visit the Arizona Mac User Group and read all or a lot of their reviews on all things RAID, eg, cards, enclosures, mini-SAS vs eSATA vs Firewire etc, I'll post some links at the end of this post.

I spent about 6 months researching how RAID works and what I would eventually need.

The other problem you have in Australia is the cost of this gear.

I searched a lot of online retailers located in Australia and found that back in February this year, any product available in the USA was about twice the price here.

eg, the cheapest I could get the Firmtek 4 Bay (I got the 5 Bay) enclosure here in Australia was about $1200, in the USA today, the 5 Bay enclosure still retails from Firmtek for $540

I bought mine direct from Firmtek and with postage and handling paid about $740 Australian, the catch is though, is that I bought the gear when the Aussie dollar was at $0.95, now with all the financial collapse the Aussie Dollar is around $0.65, so if you buy from overseas at present, you're going to pay a 30% premium on the dollar than at the beginning of the year.

Anyway, I filled the 5 Bay enclosure with 5 x WD 500 AAKK HD's, which gives me 2.3 TB system and with the cost of the PCIe RR Card, all up it worked out to approximately $0.66 a GB.

I had one drive fail within the first week, but so far everything is working well.

I just have the thing at RAID 0, all speed and no redundancy, but I'm thinking of going RAID 5, I'm still a little nervous about that first drive failure so soon and I am only using a Canon HF10 camera at present and it only captures video at 15 mb/sec, however I hope to be using a Sony EX 3 soonish and they capture video at 35 MB/sec to memory card. So the performance hit going RAID 5 is about 20%.

Anyway, here are some links to AMUG and one Australian online retailer: Good luck!

Incidently, AMUG review all different types of RAID gear, I don't work for Firmtek, it just appeared best value for money for me at the time

http://www.amug.org/amug-web/html/amug/reviews/articles/firmtek/5pm/

http://www.amug.org/amug-web/html/amug/reviews/articles/highpoint/2314/

http://www.firmtek.com/seritek/seritek-5pm/

http://www.epowermac.com.au/prodtype.asp?PT_ID=181&strPageHistory=cat

offshore

 

[CarlsonCustoms]

I guess I'll chime in here.

I just bought a Areca 1220 Hardware raid card. It has 8 SataII ports, is PCIe bus powered, and is around $450.

I'm using it in linux for a file server but in the directions it has instructions listed for mac osx so I'm assuming it should work in a mac pro but don't quote me on that.

I filled it with 5 1tb Seagate 7200.11 drives that were around $130 a piece.

This setup is a LITTLE overkill but I think the performance is worth it and the redundancy is what I was hoping for.



The reason I went with a h/w card was after frustrating attempts with the ICH10R "onboard h/w" raid that my mobo offered. It was atrocious.

I also tried a promise fastrax "fakeraid" card that came with a server I bought.. It was terrible too


I know the areca card is pricey but they do offer a 4 port card for $300 if you are on a budget.

Zack