WD 2TB Caviar Black - No Raid in Mac Pro?

[DoFoT9]

Yes. All the RE versions have the 7,0 timing by default, and they can be adjusted with the TLER utility (though some that've tried didn't see how to adjust the actual values, just set it on/off; but it is possible). It's an old tool afterall, and has to be done via a command line (so it's not as easy as a GUI).

does seem quite old, but useful i guess. turning it on/off seems useful enough - youd assume the RAID cards are well within that spec and wouldnt interfere with it at all

Keep in mind, my choices are based on reliability first, performance and cost after (they can change, depending on need).

I look at it this way; A super fast or cheapest capacity disk is useless if it's going to fail on me in less than 3 years of use (additional time is better of course, but I plan on a 3 year MTBR). So if they fail prior to that, they're not a bargain to me (I don't want to have to deal with RMA's, swapping out bad disks,... prior to planned instances).

100% agreed there - these drives will be going in a file server which will likely be on 24/7, it will be used for various things but the drives are likely to have low-medium range write cycles, the aim here is certainly to have the lowest power drives but reliability is of uptmost importance.

ive seen ~$50 drop in 2TB drives, and 3TBs are nearly out in all consumer shops - ill be waiting another month or 2 for the prices to drop sub $100 and then i will invest i just can understand why the hitachi are ~$30 more expensive then Samsun/Seagate/WD but are worse?

 

[lbeck]

It is one backup because you made it at the same time, and it is in the same place. It is a very good backup, but it is one backup in my mind. If the enclosure craps out, then what? If you delete a file by mistake, then make a backup, what happens? I'd almost rather raid1 my working drive (so I had an immediate backup of everything I did) and rely on a single backup when I knew things were good. But that is me, and like I said, everybody has a different idea of how to backup. In case you care, what I do is nightly
backup to a local drives (turned on as needed), and occasionally backup to off-site drives. I also use time machine to backup some stuff automatically. Again it is not perfect, and it may not work for you.

If you raid 2x2tb disks (for the space) how does your backup deal with that? Are your backup disks 4tb (if so, where can I buy them), or do you not plan to fill your working disks.

Not trying to cause problems, just discussing things

No problem at all, glad we're discussing it. This is what I wanted.

I see your point about one backup. If the enclosure failed then I assume I can remove the drive or drives and plug them in elsewhere and they should work as long as they did not fail. Maybe I'm wrong for assuming that.

I also see your point about deleting a file then backing up and deleting in on my backup. That may be an issue for some but not for me since I'm a OCD file organizer and check to make sure I didnt do something like that before my nightly backup. Although, Im thinking about how I may change my backup system.

I like my external backup to be identical to what is on my Computer, which is why I use RAID1. And I like the idea of my backup having an identical backup. Ive had this type system for about 5 years and have never had issues so I'll probably stick with it. But I like the idea of having a "true" second backup so I'm not sure what I'll do. Maybe just buy a second enclosure.

Rigth now I have an old OWC enclosure and need to get a new one that supports higher capacity. I'm looking at the one you posted from OWC, the 8TB model. But if I use RAID1 it will only give me 4TB, which will work for now but not for the future. Definitley need to think about whats best in the long run since I'm upgrading my internal capacity and need to do the same for my external backup.

 

[SkyNite]

I liked the idea of having my OS look like its one drive for all my business files but if its not as secure then maybe I'll just not use any RAID at all. MY external backup system is Mirrored RAID 1 so I have two backups of everything.

So do you recommend not using RAID 0 then? If I dont use RAID 0 then my backup process will take longer since CCC can only backup one drive at a time, right? I'd have to back up one drive, then go to the next and next. Or is there an easier way to do that?

CCC can schedule as many backups as you like; check out CCC's Scheduled Tasks window. And the backups can run concurrently IIRC. At any rate, scheduling the backup tasks for the middle of the night makes this a non-issue for me.

IMO having a different boot disk (a SSD) and data disk for my home directory is not a big deal at all.

 

[nanofrog]

I like my external backup to be identical to what is on my Computer, which is why I use RAID1. And I like the idea of my backup having an identical backup. Ive had this type system for about 5 years and have never had issues so I'll probably stick with it. But I like the idea of having a "true" second backup so I'm not sure what I'll do. Maybe just buy a second enclosure.

You can do this with software, including by making a clone. If you want a second copy on-site, then direct it to 2x different locations (i.e. separate external enclosures if needed).

Rigth now I have an old OWC enclosure and need to get a new one that supports higher capacity. I'm looking at the one you posted from OWC, the 8TB model. But if I use RAID1 it will only give me 4TB, which will work for now but not for the future. Definitley need to think about whats best in the long run since I'm upgrading my internal capacity and need to do the same for my external backup.

You'd probably be best served by going with an eSATA card + external PM enclosure. It's the least expensive way to attach mass storage when the internal locations are all filled (PM enclosures can usually be found in 4, 5, 8, or 10 bay versions, so it may be possible to fit both backups in the same enclosure, depending on drive capacities used).

 

[lbeck]

Awesome, thanks for all the info!

Nano frog, I'm curious ... Do you use a SSD for boot? And if so do you keep your user folder on your boot drive?

 

[DoFoT9]

You'd probably be best served by going with an eSATA card + external PM enclosure. It's the least expensive way to attach mass storage when the internal locations are all filled (PM enclosures can usually be found in 4, 5, 8, or 10 bay versions, so it may be possible to fit both backups in the same enclosure, depending on drive capacities used).

you. are. so. bad. at. timing!

here i am all ready to purchase an ANTEC TWELVE HUNDRED - which can hold ~12hdds for about $215, and along you come with a solution that may be ok for me. i dont know what to do now! is there a cheaper way to do this but still let it connect via eSATA?

1. purchase computer case
2. purchase hdds
3. purchase RAID card
4. ??
5. connect via eSATA to comptuer

or would it just be cheaper/easier going with the case above (or similar)?

 

[nanofrog]

Awesome, thanks for all the info!

Nano frog, I'm curious ... Do you use a SSD for boot? And if so do you keep your user folder on your boot drive?

No, I use mechanical drives attached to RAID cards (2x cards; both are used in RAID 5, but one is SATA, the other SAS). Most of my files are large (requires fast sequential throughput), so random access throughput isn't a primary need (nice to have, but something I can compromise on). SSD's aren't well suited for RAID 5 (any parity based array) due to the write cycles (parity data + primary data), and are too expensive for the capacity. I expect this will change, but it will be awhile before the capacity is low enough I can re-examine SSD's for my primary usage. I may get one for a boot disk later (Velociraptor works just fine), but I'll wait until it's time to replace it first.

BTW, you can't sleep with RAID cards under OS X, so it has to stay on, or be shut down. Windows 7 has allowed the cards to sleep so far, but that's not been the case in the past, and could change with an update (XP or Vista don't allow sleep to work with RAID cards either).

you. are. so. bad. at. timing!

here i am all ready to purchase an ANTEC TWELVE HUNDRED - which can hold ~12hdds for about $215, and along you come with a solution that may be ok for me. i dont know what to do now! is there a cheaper way to do this but still let it connect via eSATA?

1. purchase computer case
2. purchase hdds
3. purchase RAID card
4. ??
5. connect via eSATA to comptuer

or would it just be cheaper/easier going with the case above (or similar)?

Well, they're not that similar.

You're trying to build a SAS/SATA enclosure run off of a proper RAID card (you're still missing some odds and ends, such as a PSU and the necessary adapter board and internal cabling), vs. an eSATA card + PM enclosure.

The throughputs possible are quite different, as the RAID card (assuming you intend to go with one port per disk) can product much faster throughputs than the PM enclosure (one port shared by all disks; what the PM chip does for you).

So will you be happy with say 250MB/s max for the eSATA + PM enclosure (based on 3.0Gb/s mechanical disks; you'd hit the wall with as few as 3x disks, assuming they're capable of 100MB/s each, and configured in a stripe set), or do you need more than that?

If you need more, or need parity, then you'll have to go with a RAID card.

But how do you plan on attaching this to an iMac? Or is it for a different system (hacked or otherwise)?

 

[DoFoT9]

Well, they're not that similar.

You're trying to build a SAS/SATA enclosure run off of a proper RAID card (you're still missing some odds and ends, such as a PSU and the necessary adapter board and internal cabling), vs. an eSATA card + PM enclosure.

The throughputs possible are quite different, as the RAID card (assuming you intend to go with one port per disk) can product much faster throughputs than the PM enclosure (one port shared by all disks; what the PM chip does for you).

So will you be happy with say 250MB/s max for the eSATA + PM enclosure (based on 3.0Gb/s mechanical disks; you'd hit the wall with as few as 3x disks, assuming they're capable of 100MB/s each, and configured in a stripe set), or do you need more than that?

If you need more, or need parity, then you'll have to go with a RAID card.

But how do you plan on attaching this to an iMac? Or is it for a different system (hacked or otherwise)?

hmm so building it separately probably isnt the best idea then, due to all those added extra costs. i had a look for the SANS Digital towerRAID and i cant seem to find any in Australia - so shipping it over isnt really realistic at this point in time.

oh - sorry, well the plan was to reuse my "Hackintosh" (E4600 CPU, old school i know) parts and take them from their 2bay beige case and put them into a ANTEC TWELVE HUNDRED, add in a few internal SATA port multiplyers and create some software based RAIDS for my storage. the possibility of having a potentional 12 bays for $200 is almost too much to miss up as i already have the PSU, RAM, mobo and CPU from the old Hack. ubuntu would be the host os (10.04 server LTS).

now if the possibility came along to keep the Hack (also has dual boot 10.04) in the beige case, attach an eSATA card, and purchase one of these TowerRAIDs - then i may consider that, as it will be utilising a hardware RAID - much better then any software RAID that i would have created myself. speed is not important, as ethernet will be the limiting factor (this will be acting as a file server).

 

[nanofrog]

hmm so building it separately probably isnt the best idea then, due to all those added extra costs. i had a look for the SANS Digital towerRAID and i cant seem to find any in Australia - so shipping it over isnt really realistic at this point in time.

Australian Distributor = Monstamac.com.au

oh - sorry, well the plan was to reuse my "Hackintosh" (E4600 CPU, old school i know) parts and take them from their 2bay beige case and put them into a ANTEC TWELVE HUNDRED, add in a few internal SATA port multiplyers and create some software based RAIDS for my storage. the possibility of having a potentional 12 bays for $200 is almost too much to miss up as i already have the PSU, RAM, mobo and CPU from the old Hack. ubuntu would be the host os (10.04 server LTS).

now if the possibility came along to keep the Hack (also has dual boot 10.04) in the beige case, attach an eSATA card, and purchase one of these TowerRAIDs - then i may consider that, as it will be utilising a hardware RAID - much better then any software RAID that i would have created myself. speed is not important, as ethernet will be the limiting factor (this will be acting as a file server).

Either would be possible.

To get started, how much throughput do you need, and what kind (random access or sequential)?

This will let me know if a PM enclosure is viable, and if you will need 6.0Gb/s (i.e. want to stripe some SSD's).

 

[DoFoT9]

Australian Distributor = Monstamac.com.au

ohh thanks very much! they kind of look new, and dont have SANS in stock, but i might shoot them an email!

To get started, how much throughput do you need, and what kind (random access or sequential)?

the main purpose will be a file server, for backing up movies, serving movies (ripped BD discs, so 5MB/s should be enough for that), holding iTunes library, and things like that. it is likely that all these may be going at once to various computers around the house. redundancy will be important, but throughput not so much - id be happy with 50MB/s at this point in time, the max would be ~70MB/s anyway as the filesever will be pluggeed directly into a GBoE switch.

does this help at all?

 

[nanofrog]

ohh thanks very much! they kind of look new, and dont have SANS in stock, but i might shoot them an email!

Worth a shot. Worst case, you could look into provantage.com, as they will ship internationally (last I checked). Not sure about shipping, but as the cost should be lower, the taxes should be as well (unless they tax the shipping too; not sure on this one).

I wish products were easier for you to get (cheaper too, as Australia seems to get ripped on everything electronic from what I can tell).

the main purpose will be a file server, for backing up movies, serving movies (ripped BD discs, so 5MB/s should be enough for that), holding iTunes library, and things like that. it is likely that all these may be going at once to various computers around the house. redundancy will be important, but throughput not so much - id be happy with 50MB/s at this point in time, the max would be ~70MB/s anyway as the filesever will be pluggeed directly into a GBoE switch.

does this help at all?

Yep.

If you want to go external, a PM enclosure and eSATA card will do nicely.

If you choose to go with the Antec case (move the hack's main board,... to the Antec), you can get a non-RAID HBA (Host Bus Adapter; you can get up to 24 ports on a single card) or a coupe/few SATA cards if you can afford/have necessary slots.

As per how to do it (either the Antec or keep the hack in the current case), JBOD might be a good way to go, if you stick with OS X. One of the ZFS levels would also be possible if you go with Linux (JBOD too, but you have additional options that won't require a RAID card, as Z-RAID/Z-RAID2 don't have the write hole associated with levels 5/6, but have the same redundancy respectively <may save you a lot of time if you get a bad disk, so the recovery options might be something to consider>).

Cost is the hard part, as I've no idea what things really go for there to say which would be the cheaper way to go.

 

[DoFoT9]

*info*

thanks nano, would you like to keep this in PM so we dont keep this thread OT? cheers

 

[beaker7]

FWIW, I've been running a 4 drive RAID 0 using consumer level Seagate 7200.xx series for 4-5 years on a Mac Pro using Disk Utility. It is backed up hourly but I have never once had a disk drop out. Note that the disks have been replaced/moved to another machine within that 4-5 years, but in general I have not seen a disk fail due to it being consumer-grade in a software RAID 0.