Questions about home network NAS setup

[EscapeYourMind]

Hello,

I have been trying to figure out the best way to add a NAS solution to my home network. The main goal of my NAS is to act as a centralized file server for my various PC's, HTPC's, tablets, etc. Primarily serving up media for the HTPC's, but also as a backup/extended storage for the PC's. Since this will be storing my media library I also want to make sure it is backed up in case something happens to a drive or the NAS.

I am aware of the "RAID is not a backup" so I believe I need two NAS boxes to accomplish my goals. The first NAS will be the primary and will be the one storing all the files. The second one would then contain backups of the first NAS (I'm assuming I can do versioned or incremental backups here on a schedule). I understand this won't protect against theft, fire, other disasters, etc. and I am ok with that level of risk, but it should provide protection against the primary NAS failing and taking everything with it, or incorrectly deleted files, etc.

I think all of that makes sense and should be a effective solution. Now my problem is with determining how many drives to use and if RAID fits into this at all. So my questions are:

1. Is there any point in using RAID in a setup like this?

It seems like RAID 1 would waste space and since I have a backup NAS it wouldn't really provide any benefit. RAID 5 may be beneficial, but I keep reading more and more people are against RAID 5.

2. Say I don't need tons of space and could probably get by with just 2 drives in the primary NAS. Would it be worth it to use RAID 1 in the primary NAS?

I think this may be going overkill with redundancy/backup. Like I am trying to force my NAS to use RAID when it doesn't need to. It is after all network attached storage, not network attached raid.

3. Does my backup NAS need to be significantly larger than the primary if I am doing scheduled incremental backups? Or can I just get two of them that are the same size?

I'm assuming I can get 2 simple 2-bay NAS boxes put 2 x 4tb drives in them and have a pretty nice 8TB file server at home that provides redundancy and backup without using any RAID, but I don't know if that is the BEST way to accomplish my goals.

Thanks for taking the time to read all this!

 

[coxhaus]

I think 2 NAS units would be effectively the same as a RAID 1 or mirror. The second NAS unit would not be able to store vary many generations of the first unit unless it was really a lot bigger. So I think a NAS with a RAID 1 would be the cheaper solution if you want redundancy.

RAID 5 is good for not wasting a lot of hard disk space when you have a lot of drives and need lots of space. A RAID 1 wastes 50% drive space. The problem with RAID 5 is it is a serious RAID and will require a good APC battery back up. It is noisy with all the drives running. It will generate heat. RAID 5 is not to be taking lightly. I am not saying don’t do RAID 5 I just want you to realize the under taking. I have run a 6 drive RAID 5 for about 5 years at my home without major problems but I have worked with RAID system for many years. My RAID 5 was migrated from Server 2008 to Microsoft Home Server 2011 so it functions as my NAS and will perform workstation backups. I retired and converted my Server 2008 to Home Server 2011 because it was cheaper.

I don’t think there is one right answer. There are always trade offs.

 

[EscapeYourMind]

If I go with just one NAS unit how much of a concern is there that the unit itself will fail and potentially take all the data with it? That is really my only reason for thinking about getting the second unit to act as a backup to the primary. I know the RAID 1 would provide the redundancy I am looking for in case the primary drive(s) fail. But I would hate to lose everything if the unit itself fails.

 

[thiggins]

If I go with just one NAS unit how much of a concern is there that the unit itself will fail and potentially take all the data with it? That is really my only reason for thinking about getting the second unit to act as a backup to the primary. I know the RAID 1 would provide the redundancy I am looking for in case the primary drive(s) fail. But I would hate to lose everything if the unit itself fails.

NEVER trust your critical data to a single device.

 

[EscapeYourMind]

NEVER trust your critical data to a single device.

That was my feeling as well and why I believe I should probably have 2 NAS units. I guess my main question is, if I use 2 NAS units is there any point in using any form of RAID in the primary NAS unit since it will always be backed up by the second NAS unit?

 

[thiggins]

There is no "right" answer. It depends on cost to replace lost data and the amount of risk you want to take.

RAID1 in the same unit copies data continuously. Backup between NASes is usually a batch process, although some NASes now provide "real-time" sync.
So operating without RAID in the primary unit means that data created/changed between backups could be lost.

As you noted, both methods don't guard against fire and theft since they are in the same physical location.

 

[EscapeYourMind]

Thanks for the help guys! I think my data is important enough to me that it justifies the cost of having 2 NAS units. But I think my data is static enough, and I think if I did nightly incremental backups from the primary to secondary NAS that I don't need to use any sort of RAID in the primary (or secondary for that matter) NAS unit. Now I just need to figure out which NAS units to use!

 

[TonyH]

Hi,
My idea would be stay with single NAS and have a back up with another means and keep it separate(even off site). Member Stevech iterated about this issue many times taking an example how he is doing it. I am on same scheme.

 

[coxhaus]

How about backups? Redundancy does not substitute for backups. If your data is that important then you will want off site backups.

 

[stevech]

The 3-2-1 Rule of Backup

The simplest way to remember how to back up your data safely is to use the 3-2-1 rule:

3 - Keep 3 copies of any important file (a primary and two backups).

2 - Have the files on 2 different media types (such as flash/hard drive or two non-RAID-pair hard drives) to protect against different types of hazards.

1 - 1 copy should be stored offsite.

Be sure to add: keep last n versions of certain files: protect from human error.

Instead of two RAID boxes, many of us home users use a USB3 or eSATA external drive, and keep it out of sight of thieves. That satisfies some of the above. Time Backup in the NAS (many have that) takes care of versions.