Disk configuration

[Addrelyn]

Question from total n00b:

Is it possible to put x (x being 5 or 6 2TB Hard Drives) together with zfs, but without raidz?
If I loose 1 disk, I loose 1 disk and that's it.
I have not loss of capacity: 6TB drives will be 12TB capacity
I only see one disk of 12TB capacity in CIFS
I have no gain in writing/reading performances

 

[Wozzzaaa]

Question from total n00b:

Is it possible to put x (x being 5 or 6 2TB Hard Drives) together with zfs, but without raidz?
If I loose 1 disk, I loose 1 disk and that's it.
I have not loss of capacity: 6TB drives will be 12TB capacity
I only see one disk of 12TB capacity in CIFS
I have no gain in writing/reading performances

Thats what I was thinking. After upgrading ive got a bucketload of old 1tb & smaller hard drives, which I was going to use as an offline backup for the files on 12tb disk. If a disk drive DOES crash & disappear, how easy is it to find which files were stored on which disk?

 

[matthewowen01]

Question from total n00b:

Is it possible to put x (x being 5 or 6 2TB Hard Drives) together with zfs, but without raidz?
If I loose 1 disk, I loose 1 disk and that's it.
I have not loss of capacity: 6TB drives will be 12TB capacity
I only see one disk of 12TB capacity in CIFS
I have no gain in writing/reading performances

you can place them all in the pool but if you loose one disk, you'll loose all of your data. go with a raidz or raidz2. the files are written across all the drives so loosing one disk will cause you to loose all your data.

 

[Wozzzaaa]

you can place them all in the pool but if you loose one disk, you'll loose all of your data. go with a raidz or raidz2. the files are written across all the drives so loosing one disk will cause you to loose all your data.

Don't you mean some of the data? If you have many files, how can you know exactly what you have lost?

 

[matthewowen01]

no i mean all. if you don't use raidz, raidz2 or a mirror, you have 0 redundancy and if any disk fails you'll loose all your data.

the likelihood of any file not being partly stored on all drives is pretty slim, virtually nil.

 

[Wozzzaaa]

no i mean all. if you don't use raidz, raidz2 or a mirror, you have 0 redundancy and if any disk fails you'll loose all your data.

the likelihood of any file not being partly stored on all drives is pretty slim, virtually nil.

So if you have raidz set up, and you loose a drive, then you only loose some of the data?

Sorry for the stupid questions.

 

[esamett]

ZFS/Z1 is tolerant of losing 1 disk drive. ZFS/Z2 is tolerant of losing 2 disk drives. ZFS/Z3 is tolerant of losing 3 disk drives. If your array loses more than the number of drives tolerated all data is lost. If you don't exceed the tolerance you can restore your array to full functionality, assuming no more drives die during the "re-silvering" process.

If you have a handful of drives and have no interest in redundancy you can set up multiple arrays, one per disk drive for example. This would be the equivalent of adding drives to a PC, with each getting its own drive letter. Under this scenario a lost drive would only risk the data on that drive. IMHO it would be better to at least set up a couple of mirrors, half the data but at least you have redundancy. This might be an option if you have a bunch of drives of different sizes.

 

[matthewowen01]

if you have a raidz and loose a drive, you loose no data

if you have a raidz2 and loose 2 drives, you loose no data

if you just have a collection of disks in your pool not in a raidz or raidz2 or mirror, if you loose 1 you loose everything.

 

[Addrelyn]

So it will be 8TB in raidz 2 with 6 2TB disks...:)

But it's still bothering me to loose 4 TB...

 

[SoftDux-Rudi]

So it will be 8TB in raidz 2 with 6 2TB disks...:)

But it's still bothering me to loose 4 TB...

At least you won't loose 8TB worth of data if you loose a disk :)

 

[Wozzzaaa]

If you have a handful of drives and have no interest in redundancy you can set up multiple arrays, one per disk drive for example. This would be the equivalent of adding drives to a PC, with each getting its own drive letter. Under this scenario a lost drive would only risk the data on that drive.

Iam thinking of going down this road. Ive got stacks of old 1tb & 1.5tb drives lying around from various upgrades, so use these as an external offsite backup.

This way my NAS space is maximized, and a stack of old drives gathering dust are recycled.

Thanks!

 

[matthewowen01]

i don't know if it is possible through the GUI but you could make a single pool consisting of 2 vdev's, one consisting of a raidz(2) of the 1 TB drives and the other of the 1.5TB drives. you'd still have at least 1(or 2 for raidz2) disks of redundancy.

if they are old, i'd go raidz2...

 

[SoftDux-Rudi]

I would go raidz1 or raidz2 in anycase, whether the drives are old or new