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Tuz's picture
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NAS v portable hard drive
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Hi,

 

I'm about to upgrade my AV amp and I'm interested in buying either a NAS or portable hard drive.

The amp will be DLNA certified and I also own a Rita (Ruark) R4 which accepts USB. I would want a minimum of 1TB storage as I will be mostly saving flac files.

Any comments on which route is the best to purchase?

 

cheers

 

 

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RE: NAS v portable hard drive

Pro's of NAS

- Large capacities with mulitple drives available

- autobackup depending on raid level

- can be accessed by multiple dlna or network equipped devices at once (eg tv, blu-ray, av, phone, computer)

 

Cons of NAS

- more expensive

 

 

I would suggest a NAS - preferably at least a 2bay so you can have your stuff automatically backed up. You have to think about the time invested in ripping cds/dvds if you were to have a disk failure.

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RE: NAS v portable hard drive

RAID is not a backup!

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RE: NAS v portable hard drive

Better than a punch in the balls though.

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RE: NAS v portable hard drive

Paul Hobbs wrote:

Better than a punch in the balls though.

X2 

My back up also happens to be two mirrored disks in a NAS.

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RE: NAS v portable hard drive

mykspence wrote:

Paul Hobbs wrote:

Better than a punch in the balls though.

X2 

My back up also happens to be two mirrored disks in a NAS.

So how does your "backup" help when you accidently delete a file?

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RE: NAS v portable hard drive

The_Lhc wrote:

So how does your "backup" help when you accidently delete a file?

Err, the same way as yours. If I delete something from my pc it doesn't delete it from my back up, does yours? If a disk fails on my back up, there's an identical one that I hope won't fail at the same time. If it does I'll be bloody unlucky for it to happen at the same time as my pc hard drive fails. 

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RE: NAS v portable hard drive

If you delete a file - why not just undelete it? 

 

With the sheer size of media volumes the main thing to guard against is disk failure.

I certainly wouldnt want to have to duplicate my NAS's (36TB) just on the off-chance I delete a file. I have 8bay raid5 and a 4bay raid5 so I only need to use 1 drive in each to give redundancy.

 

Backup system volumes, and user data - yes.

Media - no, just raid.

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RE: NAS v portable hard drive

mykspence wrote:

The_Lhc wrote:

So how does your "backup" help when you accidently delete a file?

Err, the same way as yours. If I delete something from my pc it doesn't delete it from my back up, does yours? If a disk fails on my back up, there's an identical one that I hope won't fail at the same time. If it does I'll be bloody unlucky for it to happen at the same time as my pc hard drive fails. 

It depends what you're using your NAS for. If it's purely there as a backup device to backup your PC hard drive, then what you've said above works.

However, many people use a NAS as more than just a backup device e.g. I store all my music on it - there's no local copy on my PC. If you have a NAS with two disks in a RAID 1 (or mirror) and you delete a file, it's deleted from both disks - instantly. There's no option to restore from the other disk. Same if you get a corruption on a file - if a file gets corrupted on your mirrored disks, it's corrupted on both disks.

So RAID is not a backup - it's protection against disk failure, but it's not a proper backup for the reason above. Why's this important? Because people assume when you say "backup" this means they'll be able to get their files back from it, no matter what's happened. Clearly with RAID, this isn't the case. It's just about making sure people understand what they're protected against with RAID, and why they really still should keep another copy of their data on a completely separate disk.

As Paul correctly states though, all of the above is better than a punch in the balls.

 

The owls are not what they seem...

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RE: NAS v portable hard drive

AnotherJoe wrote:

If you delete a file - why not just undelete it? 

That might be possible. But it might not. Sure, you probably could undelete it eventually if you downloaded the software which does this and go through all that rigamorale, but I'm willing to bet this software would scare the bejesus out of a lot of people. So it's just easier to say RAID is protection against disk failure and, you should ideally keep a backup of the NAS on a separate disk if it's really important data. That way everyone knows the risks, rather than feeling a bit put out when, after they've accidentally deleted a folder completely and emptied the recycle bin, you say "oh well no, RAID won't protect you against that!".

AnotherJoe wrote:

With the sheer size of media volumes the main thing to guard against is disk failure.

I certainly wouldnt want to have to duplicate my NAS's (36TB) just on the off-chance I delete a file. I have 8bay raid5 and a 4bay raid5 so I only need to use 1 drive in each to give redundancy.

Backup system volumes, and user data - yes.

Media - no, just raid.

That's your choice because you know what you're doing. I think it's best others make their own mind up on whether their files / media data deserves its own backup or not - mainly it depends how they use their NAS. If people keep being told RAID is a backup, they might choose to store everything on their NAS alone so they know it's "automatically backed up".

On the other hand, RAID also isn't infallible. RAID systems can and do fail e.g. even if you have four disks in a RAID 5, sometimes when one fails, the RAID itself fails, and then all your data is gone. It's uncommon, but it's happened to me at work at least three of four times in my career. Fortunately, we've always had a backup to fall back on, so the system might have been down for a bit, but no real harm was done. So for home, I know I don't want to have to rip all my CDs again, so, even though chances are minimal that I lose the data on my NAS, £80 spent on one 2 TB disk to keep them safe in a cupboard is worth knowing that pain won't have to be repeated.

 

The owls are not what they seem...

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RE: NAS v portable hard drive

Agreed Prof, I just get bored when people spout the old "raid is not a back up" line with no other explanation. As you've said, it depends what you use it for.

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RE: NAS v portable hard drive

mykspence wrote:

Agreed Prof, I just get bored when people spout the old "raid is not a back up" line with no other explanation. As you've said, it depends what you use it for.

But then, RAID is not a back up!  :poke:

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RE: NAS v portable hard drive

bigboss wrote:

But then, RAID is not a back up!  :poke:

 

PMSL, I have a nas as a back up, it happens to be a raid array. If one disk fails the other has a copy of the data.  I think what you mean is, raid isn't always a back up? Not sure what :poke: means.

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RE: NAS v portable hard drive

mykspence wrote:

Not sure what :poke: means.

Jus' pokin' because

mykspence wrote:

I just get bored when people spout the old "raid is not a back up" line with no other explanation.

Smile

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RE: NAS v portable hard drive

professorhat wrote:

 even if you have four disks in a RAID 5, sometimes when one fails, the RAID itself fails, and then all your data is gone. 

 

Only if you dont have a UPS or battery backed cache.

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RE: NAS v portable hard drive

AnotherJoe wrote:

professorhat wrote:

 even if you have four disks in a RAID 5, sometimes when one fails, the RAID itself fails, and then all your data is gone. 

Only if you dont have a UPS or battery backed cache.

Nope, the systems at work that failed all ran off a UPS and had a battery backed cache built into the RAID card. Essentially, when the disk failed, it also caused the RAID card itself to get into a mess which meant it lost the config and had to be rebuilt. Naturally this meant the data had gone. Yes, it may well have been possible to get the data off using data recovery tools, but the point is, why put yourself through the risk of all that hassle for the sake of a cost of another disk to backup all your files? Also, I appreciate this was quite a few years ago and I'm sure the RAID technology used today is more robust, but I wouldn't want to risk it personally.

I appreciate you have a 36 TB NAS (though god knows what you store on it to use that much space!) and so this makes it more difficult to backup and you therefore choose not to since it's only media files and therefore you don't think it's worth it. But it's pretty unusual for most home setups to have anything more then 4 TB which can easily be backed up on to a couple of 2 TB disks for not a lot of extra money.

The aim really should just to give people accurate info and let them make up their own mind whether they want to invest in a separate backup just in case, or take the small risk they might lose it should the worst happen.

 

The owls are not what they seem...

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