5 bay NAS for backup

[tmanto02]

Hi guys,

I have quite a large movie and tv collection spread across 4 x 2tb external FireWire hard drives. One of the drives failed last week so I am looking into getting a NAS for redundancy.

I struggle to understand all the different types of raid configurations, however I am looking for a solution so that if one drive fails I can simply swap the drive over with a healthy one.

Does it sound like I need a 5-bay NAS that supports raid 5 configuration?

I would most likely use 5x 2tb drives, however as my movie collection grows is it possible to replace each drive with 4tb drives one by one?

Cheers

 

[flynz4]

RAID 5 (or any RAID) can often be repaired after an individual disk failure/replacement... but it is not foolproof. In fact, a RAID array (while solving some failure mechanisms)... introduces new failure mechanisms that do not exist in regular non-RAID storage.

If this data is important to you, then you need backup, not RAID. RAID is very much not backup. Backup is still needed.

/Jim

 

[FreakinEurekan]

Agree that RAID does not replace the need for backups... But still it's nice not to have to rebuild/restore the whole drive set when a disk fails, so I'd still do RAID. Look at Drobo, it lets you migrate easily to larger disks as needed.

 

[tmanto02]

RAID 5 (or any RAID) can often be repaired after an individual disk failure/replacement... but it is not foolproof. In fact, a RAID array (while solving some failure mechanisms)... introduces new failure mechanisms that do not exist in regular non-RAID storage.

If this data is important to you, then you need backup, not RAID. RAID is very much not backup. Backup is still needed.

/Jim

Yeah I completely agree, ideally I would love to backup all of it but it's just too expensive. That's why I was considering raid 5 so at least if 1 drive fails I can rebuild the raid.

 

[tmanto02]

Agree that RAID does not replace the need for backups... But still it's nice not to have to rebuild/restore the whole drive set when a disk fails, so I'd still do RAID. Look at Drobo, it lets you migrate easily to larger disks as needed.

Thanks mate, yes I have seen drobo before, I didnt initially want to spend that much for a diskless DAS but looks like i might have too

 

[ColdCase]

tmanto, do you think this is easy to recover a RAID set from a drive failure? Are you aware of the fine print in the marketing literature? With the exception of mirroring, which I don't think you are talking about here, when you replace a drive in a RAID set, it may take days, if not a week for the RAID processor to rebuild. During that time you do not have RAID fault tolerance or performance, although you can get stuff on and off the RAID set, performance will be dog slow.

RAIDs made more sense back when drives cost real money, but now they are more useful for performance than redundancy (unless you are straight mirroring). Even then you may not notice one of the mirror drives going south until both fail.

Just saying that you may be shooting yourself in the foot by forcing a RAID solution on your dilemma. A good RAID controller is not cheap, you can probably buy two 4TB in drives for the same $$.

Oh and most RAID5 controllers must have all drives the same size (well if you install a larger size the excess is not used). There are some concatenating type RAIDs that you can add more drives of differing capacity, but when you replace the RAID will rebuild (oversimplified I know).

For storage of a large home video library that exceeds 3 or 4 TB, typically its easier to use a RAID (hardware or OS) to combine drives. And then a second RAID set to backup the main library. RAID5 is probably not the best thing for you, RAID 10 perhaps.

 

[tmanto02]

tmanto, do you think this is easy to recover a RAID set from a drive failure? Are you aware of the fine print in the marketing literature? With the exception of mirroring, which I don't think you are talking about here, when you replace a drive in a RAID set, it may take days, if not a week for the RAID processor to rebuild. During that time you do not have RAID fault tolerance or performance, although you can get stuff on and off the RAID set, performance will be dog slow.

RAIDs made more sense back when drives cost real money, but now they are more useful for performance than redundancy (unless you are straight mirroring). Even then you may not notice one of the mirror drives going south until both fail.

Just saying that you may be shooting yourself in the foot by forcing a RAID solution on your dilemma. A good RAID controller is not cheap, you can probably buy two 4TB in drives for the same $$.

Oh and most RAID5 controllers must have all drives the same size (well if you install a larger size the excess is not used). There are some concatenating type RAIDs that you can add more drives of differing capacity, but when you replace the RAID will rebuild (oversimplified I know).

For storage of a large home video library that exceeds 3 or 4 TB, typically its easier to use a RAID (hardware or OS) to combine drives. And then a second RAID set to backup the main library. RAID5 is probably not the best thing for you, RAID 10 perhaps.

Thanks for your advice. I went with the drobo 5n in the end. It should arrive tomorrow. That way I can use mixed drives initially until I can afford to fill it with 4tb WD red drives.