One dual drive Vs two single drive NAS for home use?

d000hg

I'm wanting to set up home NAS for:
Central store for music and video filesCentral network disk driveBackup to cloud of photos and critical filesI assume we'd have cloud backup but this is of little help in case of failure.

My question is all other things being considered, would you prefer a single dual drive (mirrored RAID) NAS, or two separate single drive units e.g one in the house, which performs backups to another in the garage... And why?

Sloppy Bob

The mirrored NAS isn't backup.

If you delete or overwrite anything off the one drive by mistake, it deletes it off the other, you don't have another copy as you were using the mirror as backup.

If the NAS fails what do you do?
If it gets stolen or there's a fire what do you do?

RAID is redundancy, not backup.

I'd also add a single drive isn't much space if you have a good sized video collection. A single ripped Bluray, for example, is averaging 25-30GB, UHD is 40GB

d000hg

Exactly, hence my question. With a limited budget for home use, which compromises make most sense?

Critical files will be backed up in the cloud but rebuilding from cloud backup would take days so redundancy reduces the chance of having to take the NAS offline but a 2nd line NAS means it's easier to rebuild if it does happen.

Sloppy Bob

Does the backup have to be a NAS?

It can just be an external HDD which is far cheaper.

d000hg

I'm new to this but if I'm using a backup app on the primary NAS, can the backup destination be pretty much anything? If so, an external drive could work. In fact I could have two so one is always kept safe and swap them weekly or something, would that work?

Abacus

4 Bay (Or more) NAS set up as Raid 6, 2 External HDD for backup with one kept off site and rotated monthly, (Sooner if you add a lot of files in one go) and a full back up to the cloud.

Bill

DannyBoy1

Think about how important it is to back stuff up, I've a single drive 3tb nas it's alway bloody 95% full and 85% of that is movies/tv shows i'll never watch again the other 10% if it were lost really wouldn't bother me, the great thing about the NAS is it's a beautiful sleek way of adding tons of storage to your system wirelessly, just hook it up to your router, spend 3 full days trying to figure out how to use it and BAM!!- no more worrying about file size. What is it that's so important to back up?

mickevh

I generally council that this is something of a value judgement and there's no "one size fits all" solution. What to do depends on the risks to be mitigated, the budget available and how important maximising available storage is.

As discussed by others, RAID isn't backup - it avails continued access to data in the event of a HDD failure (they all die in the end) at the the price of less storage for the money. But it doesn't mitigate accidental deletion, malware, theft, failure of the host device, etc. etc. For a business, continued data access is crucial so we use RAID, but for a home movie tank (where you have the original media) one might prefer to maximise available storage.

"Backup" generally means making a duplicate "somewhere else." How often to make such a backup, how long to retain them and where to keep them (onsite, offsite, both,) is another value judgement again base on the risks to be mitigated and cost. As explored previously, backing up critical data to an cloud solution mitigates lots of risks for the local environment (flood, theft, host failure, etc.) but can take a while to run (especially the first one) and can take an age to restore. (BTW, don't forget most SOHO ISP packages have much lower upload rates then download.)

And as we often opine in these columns, very many people (and way too many businesses) never test out restoring from their backups - the time to find out your backups don't work is not the day you've deleted the wedding video or the household budget spreadsheet.

Of course, there's plenty of scope to mix and match solutions, especially if you are a bit creative about how you organise the data. For example, all the DVD/BD rips - you have the originals on platter and loosing them isn't the end of the world, so don't bother backing them up and maximise your storage. Elsewhere, your word docs and spreadsheet are critical and irreplaceable, (and relatively small) so maybe backup that share to a cloud storage solution - many ISP's now offer you a fair wodge of cloud storage for free.

And the more you can automate the better - backing up data is a miserably boring task and really easy to find an excuse to not do it. Even if you automate, you still need to check it's happened from time to time (and ideally test restoring something.)