Do I need a RAID setup?

[sachman]

MY knowledge of RAID is minimal to basic.

My setup is an iMac - 1TB with 70gb free
I have 2 external HDs which I use for storage rather than back up - they are clones of each other- made manually rather than with an application. They have 600Gb on it

I have another HD for backing up the imac using carbon copy cloner


I hate the above setup and carbon copy cloner
I want a big HD to use time machine on.
I know I will soon need another 2 HDs for further storage and backup

Can RAID do all of the above - ie for storage and backup if I get a big one like 5TB?

Most files are videos / photos / games

Thanks for your advice

 

[matreya]

No, RAID is for redundancy, to reduce downtime by keeping files available when a hard drive fails, so you can buy a new hard drive mechanism to rebuild the RAID array in the event of a drive failure.

Also, if you're using a drive as storage AND backup, then it's not a backup.

I use CCC to maintain a RAID5 array clone of another RAID5 array. Works very well for me.

The following unit, when configured for RAID5, will provide 6TB of space.

https://eshop.macsales.com/item/OWC/M3QX2T08.0S/

Alternatively, if you want Thunderbolt:

https://eshop.macsales.com/item/OWC/TB2SRT08.0S/

 

[sachman]

I'm still not understanding when RAID is required. If a Hard drive fails and you have a bootable external HD then the downtime is minimal anyway, so what advantage does RAID have?

Those a out of my budget, I was looking at this https://www.amazon.co.uk/Thunderbol...id=1504539738&sr=8-5&keywords=raid+hard+drive

 

[Erdbeertorte]

RAID 0 is for merging the drives to gain speed and is shown as one disk with the size of the smallest in there. If one of them fails everything is lost.

RAID 1 keeps the same data on both drives by mirroring them. So if one of them fails you can just replace that one and nothing will be lost.

RAID 5 is the same as RAID 1 just for more drives.

JBOD (just a bunch of disks) is like RAID 0 but you can use the storage amount of all drives merged together, without gaining speed.

There are some more RAID modes but those are the most common ones.

 

[ZapNZs]

I'm still not understanding when RAID is required. If a Hard drive fails and you have a bootable external HD then the downtime is minimal anyway, so what advantage does RAID have?

Those a out of my budget, I was looking at this https://www.amazon.co.uk/Thunderbol...id=1504539738&sr=8-5&keywords=raid+hard+drive

My understanding of RAID is less than other posters on this forum.

Different RAID levels have different advantages - some are speed, some are protection against data loss from a physical disk failure, some are convenience/reduced downtime when a drive failure does happen, some are economy (combining multiple smaller drives to appear as a single larger drive is often more economical than purchasing one super high capacity drive), and some are a combination of these factors.

For example, let's say you purchased a hard RAID 5 enclosure with 4 drives, and you kept your Time Machine, your CCC clone of the local disk, and the unique data storage you do not have on the local OS drive on the RAID 5 setup. If one day, one of the drives were to fail, then you would remove the failed drive, put in a new drive, and over a period of several hours this new drive is repopulated and you do not lose any data at all. This RAID 5 setup gives what is called a 'one disk redundancy' - that is, one drive can fail, and you will not lose any data. The recovery is much simpler than manually copying the files because the system itself rebuilds that failed disk. Additionally, during the rebuilding process, the amount of computer resources being used can be much less than with manually rebuilding, leaving the User with the ability to continue their normal workflow during the rebuild process. Some RAID levels/setups will yield more than one disk redundancy, where as RAID 0 does not yield any redundancy (i.e., if one drive fails, all of the data is lost.) However, a single RAID volume on its own is not a backup solution because it protects against physical disk failure but not other causes of data loss.

With what you are doing, the RAID setup that might benefit you could be a RAID1 for the two disks you are currently manually making clones of - when you save a file to one, it will automatically be saved to both. If you want to have a single enclosure to replace multiple enclosures (there are some risks with this), for this, you could purchase a 4-bay enclosure (such as some of the empty enclosures OWC offers) where you would house your 2 existing drives in a soft RAID 1 for the storage of the unique data, the 1 drive currently used for Carbon Copy Cloner, and a very large drive (such as a 6TB HGST DeskStar) that is used for Time Machine to backup both the local OS disk and the RAID1 volume. Depending on the age of your existing drives, it might or might not be advisable to replace them at this point. If they are younger, SMART says in good health, and still large enough for your needs, then there is no reason you cannot continue to use them in combination with a large Time Machine volume. By using Time Machine to back up the RAID1, you get protection against several types of data loss that RAID in and of itself cannot protect against.

 

[matreya]

I'm still not understanding when RAID is required. If a Hard drive fails and you have a bootable external HD then the downtime is minimal anyway, so what advantage does RAID have?

RAID ensures you still have your data, despite a drive failure. RAID is no substitute for a backup.

Those a out of my budget, I was looking at this https://www.amazon.co.uk/Thunderbol...id=1504539738&sr=8-5&keywords=raid+hard+drive

This drive will only offer you 3TB of space if you use it in RAID1 (mirror) mode. If you use it in RAID0, then if one of the drives fails, you lose all the data.

 

[throAU]

MY knowledge of RAID is minimal to basic.

My setup is an iMac - 1TB with 70gb free
I have 2 external HDs which I use for storage rather than back up - they are clones of each other- made manually rather than with an application. They have 600Gb on it

I have another HD for backing up the imac using carbon copy cloner


I hate the above setup and carbon copy cloner
I want a big HD to use time machine on.
I know I will soon need another 2 HDs for further storage and backup

Can RAID do all of the above - ie for storage and backup if I get a big one like 5TB?

Most files are videos / photos / games

Thanks for your advice

There are 2-3 reasons to run RAID:
- improved speed beyond what a single drive can offer
- fault tolerance, so your data will stay operationally available during a drive failure until you can replace a drive
- more space in a contiguous single area beyond what a single drive can offer

RAID is not backup. RAID will not protect you against
- deleting stuff
- theft of your device
- filesystem corruption (malware, virus, software bug, etc.)

You can use a RAID box as a backup destination - that's a good use of RAID.

Just don't rely on RAID on your main system as primary storage to think that you no longer need a second or third copy of your stuff that is physically seperate from your production storage (and ideally off-site).

If it sounds like RAID is of limited usefulness to a typical end user these days, you would be correct.

With fast SSDs and large drive capacities, the need for RAID for speed and more space is diminishing for single users because SSDs are fast enough and single drives are large enough for the most part today.

RAID today is more useful on servers that provide for multiple users or virtualised environments where many machines are run off a single storage box. RAID on single user machines is becoming more trouble than it is worth - because you still need a backup. RAID won't eliminate your need to back up.

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RAID 0 is for merging the drives to gain speed and is shown as one disk with the size of the smallest in there. If one of them fails everything is lost.

RAID 1 keeps the same data on both drives by mirroring them. So if one of them fails you can just replace that one and nothing will be lost.

RAID 5 is the same as RAID 1 just for more drives.

JBOD (just a bunch of disks) is like RAID 0 but you can use the storage amount of all drives merged together, without gaining speed.

There are some more RAID modes but those are the most common ones.

RAID0 is shown as <number of drives> X <size of smallest drive in RAID set>

RAID 5 is not the same as RAID 1, it costs you less data as it does error detection and correction via distributed parity, not a complete copy of the data.

RAID0 isn't the only RAID level that can provide improved speed. It is the fastest RAID though, but doesn't really deserve to be called RAID (some call it striping instead). RAID stands for "redundant array of inexpensive disks" and RAID0 provides no redundancy.

 

[sachman]

ok thanks for all your replies. It doesn't look like RAID offers much benefit backing up wise except faster reboot which isn't all that important to me as it's home use.

The other thing is video editing, most of my large files are videos and editing I've done. Would a RAID help with that. My machine is a limiting factor as I shoot in 4K and can barely render. I've freed some space on my internal HD (not a SSD). Would a RAID via thunderbolt run these videos on FCP or imovie better than a normal external HD through thunderbolt or my internal HD (I only have 100gb free on 1TB)?

Many thanks

 

[Nick Milner]

RAID arrays are pretty cheap these days. If you want a setup where you can carry on working even in the face of a drive failure then a simple RAID 1 setup is easy and cheap to acquire. This means no downtime after the failure and no potential for lost work since your last backup. But do bear in mind the caveats listed above.

 

[matreya]

Would a RAID via thunderbolt run these videos on FCP or imovie better than a normal external HD through thunderbolt or my internal HD (I only have 100gb free on 1TB)?

I've already recommended a Thunderbolt RAID solution (RAID5) that would be considerably faster than a normal external hard drive, but you've said you cannot afford it.

 

[hfg]

Just for fun I ran the BlackMagic DiskSpeedTest on my ThunderBay 4 connected via a adapter to a 2017 iMac 5K i7. It has 4 standard Seagate 3TB drives in a SoftRAID 5 configuration (it actually is configured as 3 logical RAID5 drives for TimeMachine, BootClone, and Scratch disks).

 

[throAU]

ok thanks for all your replies. It doesn't look like RAID offers much benefit backing up wise except faster reboot which isn't all that important to me as it's home use.

The other thing is video editing, most of my large files are videos and editing I've done. Would a RAID help with that. My machine is a limiting factor as I shoot in 4K and can barely render. I've freed some space on my internal HD (not a SSD). Would a RAID via thunderbolt run these videos on FCP or imovie better than a normal external HD through thunderbolt or my internal HD (I only have 100gb free on 1TB)?

Many thanks

A small number of hard drives in RAID will not be fast enough for 4k video editing. Best case scenario with RAID (i.e., RAID0) you add up the IOPs for each drive to get an idea of access speed. i.e., a hard drive will do maybe 100-150 IOs per sec. So add them up... Even a cheap SSD these days will do 10,000 IOs per sec.

An SSD will, and will be cheaper to set up.

 

[ZapNZs]

ok thanks for all your replies. It doesn't look like RAID offers much benefit backing up wise except faster reboot which isn't all that important to me as it's home use.

The other thing is video editing, most of my large files are videos and editing I've done. Would a RAID help with that. My machine is a limiting factor as I shoot in 4K and can barely render. I've freed some space on my internal HD (not a SSD). Would a RAID via thunderbolt run these videos on FCP or imovie better than a normal external HD through thunderbolt or my internal HD (I only have 100gb free on 1TB)?

Many thanks

IMO, upgrading your internal drive to a 2TB Samsung 850 PRO or EVO is going to give you the best benefit in this department. If your OS drive is a HDD, it is going to be a bottleneck regardless of your external setup, IMHO.

 

[Fishrrman]

OP wrote:
"I hate the above setup and carbon copy cloner
I want a big HD to use time machine on."

You don't want to use Time Machine for copying one EXTERNAL drive to another.
CCC works best for this. It ensures that one is the exact copy of the other.

If you don't mind setting it up and using CCC at regular intervals, it will work much better for you in "a moment of extreme need", than will TM, which often lets folks down.

Repeat the following over and over:
"RAID is not a backup".
RAID setups can be temperamental and problematic. If you are looking for "easy", look at something else.

Looks to me like what you need might be:
1. An external drive sufficient to keep your internal drive backed up.
2. An second external drive to serve as your "primary external" drive.
3. A third external drive to serve as your BACKUP to the primary external drive.

Hey -- isn't that pretty much the way things are set up right now?

 

[sachman]

I've already recommended a Thunderbolt RAID solution (RAID5) that would be considerably faster than a normal external hard drive, but you've said you cannot afford it.

So is that the only one in the world that is faster?

Fishrrman - no I would use time machine to backup my internal and I tend to manually just copy things to my 2 externals that are used for space as it's just easier to do at the time.

I think I will leave RAID as it probably isn't required.

This might be a stupid question but will an external SSD via thunderbolt 1 run/edit videos faster than my internal hard drive

 

[Fishrrman]

OP wrote:
"I would use time machine to backup my internal and I tend to manually just copy things to my 2 externals that are used for space as it's just easier to do at the time."

I have never once used Time Machine, I don't care for how it works.
I don't recommend it to anyone, though perhaps it might be useful for some.
But that's my opinion only.

"This might be a stupid question but will an external SSD via thunderbolt 1 run/edit videos faster than my internal hard drive"

If it's a platter-based drive, I would hazard a guess that, yes, it would (provided you were booting from the drive).
Again, my opinion only, but you'd do as well (or better) to use a USB3 external SSD, than thunderbolt.

 

[sachman]

OK thanks, I don't think my imac has a USB 3 port

 

[ZapNZs]

This might be a stupid question but will an external SSD via thunderbolt 1 run/edit videos faster than my internal hard drive

If you clone the existing/install a second operating system on the external SSD and run the editing App itself off of the external OS SSD, and use that external SSD as the export destination, yes (although performance will not be as good as installing a SSD in the internal drive bay.) If you are running the OS and editing App from the internal HDD and only using the SSD as a data drive, then IMO this will yield minimal performance improvements due to the HDD acting as the bottleneck.