External Storage Options

I have the WD Studio (Single) Drive and it is brilliant and reliable, no comment at all, my bro has got another WD external drive and he is very happy as well

"1- Icy Dock 2 Bay Firewire Enclosure (enclosure only) - £145"

This looks like a good deal, but -- don't RAID it.

RAID may be very fast, but creating a RAID array introduces new risks into your storage strategy -- particulary the requirement that you keep the RAID backed up against the possibility of failure. Lose one drive in the RAID, and -all- your data may be gone.

In my opinion, better to keep it as JBOD (just bunch of drives). Might be two icons on the desktop instead of one, but easier to deal with in the case of a drive failure.

Fishrrman said:

"1- Icy Dock 2 Bay Firewire Enclosure (enclosure only) - £145"

This looks like a good deal, but -- don't RAID it.

RAID may be very fast, but creating a RAID array introduces new risks into your storage strategy -- particulary the requirement that you keep the RAID backed up against the possibility of failure. Lose one drive in the RAID, and -all- your data may be gone.

Click to expand...

I am sure you are referring to RAID 0, or stripe set RAID.
In fact, RAID 1 is a mirror solution, and I think it is very well suitable for the needs of the thread starter. In this case, it is important that he/she checks the specifications of enclosures or dual drives, to be sure they support RAID 1 as well, and that RAID 1 can be set through OS X.

Enclosures normally have some kind of physical switch to determine the RAID array in use, while dual drives come with a software solution for that.

Fishrrman said:

"1- Icy Dock 2 Bay Firewire Enclosure (enclosure only) - £145"

This looks like a good deal, but -- don't RAID it.

RAID may be very fast, but creating a RAID array introduces new risks into your storage strategy -- particulary the requirement that you keep the RAID backed up against the possibility of failure. Lose one drive in the RAID, and -all- your data may be gone.

In my opinion, better to keep it as JBOD (just bunch of drives). Might be two icons on the desktop instead of one, but easier to deal with in the case of a drive failure.

Click to expand...

That is misinformation - it depends on what type of RAID he sets up. You're talking RAID 0 - just striping - which is done solely for speed. If either disk fails, you lose the whole thing. However, he could set it up as a RAID 1, which is mirrored, resulting in a built-in backup so to speak. He mentioned "data security" as being important, so RAID 1 would be great. To get both striping and mirroring, he'd set it up as RAID 5 but that requires 3 disks minimum.

RAID doesn't introduce any new risks at all - you just need to keep it backed up JUST LIKE ANY OTHER DISK. To say that it is more risky is just false. As a matter of fact, the JBOD strategy is more risky if you don't keep backups of each disk.

Mike in Kansas said:

That is misinformation - it depends on what type of RAID he sets up. You're talking RAID 0 - just striping - which is done solely for speed. If either disk fails, you lose the whole thing. However, he could set it up as a RAID 1, which is mirrored, resulting in a built-in backup so to speak. He mentioned "data security" as being important, so RAID 1 would be great. To get both striping and mirroring, he'd set it up as RAID 5 but that requires 3 disks minimum.

RAID doesn't introduce any new risks at all - you just need to keep it backed up JUST LIKE ANY OTHER DISK. To say that it is more risky is just false. As a matter of fact, the JBOD strategy is more risky if you don't keep backups of each disk.

Click to expand...

Regarding bold sections above. Striping + Mirroring is actually RAID 10. RAID 5 stripes data across 3 or more drives with parity being applied to one of them. Hence... (for example)... in a 4 drive RAID 5 array, you could operate with any 3 out of 4 drives working.

I do not think it is accurate to say that RAID does not introduce new risks. You are 100% correct that they still need to be backed up... and that backing up helps mitigate risk for all storage solutions. However, RAID (of any type) offers complexity... and new failure mechanisms do exist in all RAID solutions.

/Jim

flynz4 said:

Regarding bold sections above. Striping + Mirroring is actually RAID 10. RAID 5 stripes data across 3 or more drives with parity being applied to one of them. Hence... (for example)... in a 4 drive RAID 5 array, you could operate with any 3 out of 4 drives working.

I do not think it is accurate to say that RAID does not introduce new risks. You are 100% correct that they still need to be backed up... and that backing up helps mitigate risk for all storage solutions. However, RAID (of any type) offers complexity... and new failure mechanisms do exist in all RAID solutions.

/Jim

Click to expand...

You are correct wrt RAID 5 vs RAID 10. I confused redundancy with mirroring in RAID 5; RAID 10 is of course mirrored and striped.

My response was intended to point out the false sense of security Fishrrman espouses by keeping things on non-RAID disks vs. RAID disks. Setting up a RAID array adds complexity BUT the risk of drive failing and losing all your data exists on any system, and to suggest that RAID is bad because you need to back it up makes no sense.

He says:

"...requirement that you keep the RAID backed up against the possibility of failure. Lose one drive in the RAID, and -all- your data may be gone."

Well, lose 1 drive in your non-backed-up-external-drive arrangement and -all- your data may be gone as well. You need to back up ANY disk storage arrangement, not just RAID. If I have a RAID array or a single external drive, I still have the same risk - if a drive fails I am prone to losing my data. Therefore, I need to backup a RAID array JUST LIKE I NEED TO BACKUP ANY DRIVE.

Here's another common scenario, and it has nothing to do with hardware failure. I was editing pictures in my Aperture library the other day and the library became corrupt. So I tried to use the database utility to rebuild it but it didn't work. What saved my ass was the Aperture Vault snapshot (true, I could have used TimeMachine) that I update whenever I upload new pictures into the library.

Data corruption can happen at any time for any reason.

N

Mike in Kansas said:

You are correct wrt RAID 5 vs RAID 10. I confused redundancy with mirroring in RAID 5; RAID 10 is of course mirrored and striped.

My response was intended to point out the false sense of security Fishrrman espouses by keeping things on non-RAID disks vs. RAID disks. Setting up a RAID array adds complexity BUT the risk of drive failing and losing all your data exists on any system, and to suggest that RAID is bad because you need to back it up makes no sense.

He says:

"...requirement that you keep the RAID backed up against the possibility of failure. Lose one drive in the RAID, and -all- your data may be gone."

Well, lose 1 drive in your non-backed-up-external-drive arrangement and -all- your data may be gone as well. You need to back up ANY disk storage arrangement, not just RAID. If I have a RAID array or a single external drive, I still have the same risk - if a drive fails I am prone to losing my data. Therefore, I need to backup a RAID array JUST LIKE I NEED TO BACKUP ANY DRIVE.

Click to expand...

Mike, I think that you and I are in violent agreement. All data needs to be backed up. 100% agreement.

Often, people think that RAID 1/5/10 offers "some" level of protection. I "mostly" disagree with that opinion. It does offer some protection against HDD failure... so that is true. However, RAID (of any flavor) introduces new failure mechanisms that are not present in single drive configurations. Hence... I think there are both +/- of RAID.

What is particularly dangerous (and you and I are both saying this)... is the false sense of security people get out of RAID. This leads people to not back up their RAID array... which is very dangerous.

/Jim

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n-i-k-k-o said:

Here's another common scenario, and it has nothing to do with hardware failure. I was editing pictures in my Aperture library the other day and the library became corrupt. So I tried to use the database utility to rebuild it but it didn't work. What saved my ass was the Aperture Vault snapshot (true, I could have used TimeMachine) that I update whenever I upload new pictures into the library.

Data corruption can happen at any time for any reason.

N

Click to expand...

Nice example.

For 100% of my data... I double back up. Time Machine for local backup and great versioning... and Crashplan+ for cloud backup/versioning.

I go to extra lengths with my "personally created media" which includes pictures and home camcorder videos. For those... in addition to the backup strategy above, I use Carbon Copy Cloner to manually create rotating pairs of backups of:

1) Aperture 3 Vaults
2) Full Aperture 3 Library
3) All camcorder videos

For those... I rotate the drives every time I import new data into Aperture... or load a new camcorder video.

Generally... I am NOT a fan of manual backup... but for my media, I only do that in addition to a double back automatic backup.

/Jim