Bought a new Home NAS

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DJ Bobcat said:
Just as a heads-up... one of the reviewers on Newegg points out that installing memory purchased from some vendor other than from QNAP voids your warranty. That may not be accurate, but something to keep in mind and check on before ordering:djsmug:.
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I looked on a Qnap forum .. the Crucial is one that is known to work .. and it looks exactly like what Qnap is selling.

That and I'll throw the original memory in if I have an issue ... :)
 
I shall henceforth resort to using 8" floppies.
 
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awdj said:
Be very careful with RAID5. Even RAID6. The numbers make sense, but you won't care about how promising it appeared if you lose your data.

Please read the following pages carefully:
http://www.zdnet.com/article/why-raid-5-stops-working-in-2009/
http://www.smbitjournal.com/2012/11/one-big-raid-10-a-new-standard-in-server-storage/
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I discount the first article... outdated and inconsistent with my experience with RAID 5 before and after 2009. The second article on RAID 10 (or RAID 1+0) is a good article and I agree with what it says. To implement it though, you need at least 4 drives the same size. Steve has only 2 each of 4 and 3TB drives, so it's not an option for him at this point.

Still, I keep a second NAS because I don't trust any RAID. I've seen a RAID 5 fail to rebuild even with only one drive failure on a Dell Server, and I've seen 2 drives fail on a 5 drive RAID, which means the entire RAID failed, requiring a complete restore. Backing up to the "Cloud" as Steve intends to do is perhaps an even better alternative. My solution doesn't provide a recovery option if my whole house burns down.
 
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I wouldn't say it's outdated -- that's the point. And yes, if you read any of the drive information, the -manufacture expected- read failures are within the windows mentioned.

The fact that if ANY drive failes in RAID5, -ALL- drives in the array are now required to read from beginning to end to rebuild the array is the problem. With RAID10, even in a 12-drive array as I have here, only one single disk needs to be copied. And that's the other thing -- with RAID10 it's a direct copy. With RAID5 every bit of data needs to be re-calculated/re-constructed from the parity information, and as I mentioned, also requires every single other drive in the array to be 100% readable. It takes much longer, and it much, much more prone to error.

I agree that RAID10 may not be possible in these smaller enclosures, but just make sure you're backed up. RAID is absolutely NOT a backup, by *ANY* means. It is simply a means to keep running in the event of a failure.

If you get a virus that encrypts your data, or if you accidentally delete or otherwise mess up your files, RAID won't help you at all. This all seems obvious when pointed out, but I can't tell you how many people treat RAID as their backup solution.
 
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DJ Bobcat said:
I'm pretty sure if you want to do RAID 5, all the disks need to be the same size. Didn't Steve say he has two 2TB's now and is adding two 3TB drives? Unless that box is doing something I've never seen, I don't think RAID 5 will work.
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You are correct, Raid 5 builds a stripe based on the size of the smallest drive in the set. A Raid that does not is JBOD - which is also not reliable (as far as redundancy goes because there is no parity).

Raid 10 is good for medium to large requirements - it's striped mirrors. This may require a large amount of drives - and both sets need the same amount and size of drives. You lose 50% of your total due to needing the mirror. For cost, space, speed and redundancy for a home user, Raid 5 will be sufficient. Raid 5 looks at the total across all drives (similar size) and you lose one drive to parity. Even in Raid 10, there is some complete rebuilding (as with Raid 5).
 
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The unit also supports RAID 10 .. I need to do some research on what will work with mixed drives.
 
BTW .. which one of these is RAID 5?

RaidSpray.gif
 
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ittigger said:
You are correct, Raid 5 builds a stripe based on the size of the smallest drive in the set.
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RAID5 generally does require all drives to be the same size. If you use drives of different sizes, no drive will be used more than size of the smallest drive.

The stripe size is set by you when you create the array, and is nowhere remotely even close to the size of a disk. It's measured in KB.

ittigger said:
Even in Raid 10, there is some complete rebuilding (as with Raid 5).
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Not sure what you're saying here, but as each drive has a mirrored (sister) drive, if any one drive dies, only one drive (its' sister) will be utilized to rebuild the newly inserted drive. No parity calculation is done in this case either; just a straight clone of the sister drive.

With RAID5, every single disk in the array is fully read 100% during the rebuild, and the missing data is calculated from the remaining drives. I can't stress enough that if ANY of your drives fails to read a single bit during the rebuild, you will lose your entire array.

The benefit of RAID5 is that you have X-1 capacity, where X is the number of drives. So if you have (8) 1TB drives, you can store 7TB of data and still have any single drive fail. With RAID10 you could only store 4TB, albeit you could have up to four drive failures simultaneously, assuming that no pair of sister drives both failed.

ittigger said:
For cost, space, speed and redundancy for a home user, Raid 5 will be sufficient.
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I agree, as long as he keeps a backup of the entire array, preferably off-site. And I mean that for -any- RAID level. Although I wouldn't entirely dismiss RAID10 -- it is definitely more robust and less complicated (as far as how your data is stored.)
 
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awdj said:
RAID5 generally does require all drives to be the same size. If you use drives of different sizes, no drive will be used more than size of the smallest drive.
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That's what I said. We're saying the same thing.

awdj said:
Not sure what you're saying here, but as each drive has a mirrored (sister) drive, if any one drive dies, only one drive (its' sister) will be utilized to rebuild the newly inserted drive. No parity calculation is done in this case either; just a straight clone of the sister drive.

With RAID5, every single disk in the array is fully read 100% during the rebuild, and the missing data is calculated from the remaining drives. I can't stress enough that if ANY of your drives fails to read a single bit during the rebuild, you will lose your entire array.

The benefit of RAID5 is that you have X-1 capacity, where X is the number of drives. So if you have (8) 1TB drives, you can store 7TB of data and still have any single drive fail. With RAID10 you could only store 4TB, albeit you could have up to four drive failures simultaneously, assuming that no pair of sister drives both failed.
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With RAID10, the array can sustain multiple drive losses so long as no mirror loses all its drives .. but at a cost - 50% of the drive is lost to mirroring. We're saying the same thing here too.

Diagram for those that don't understand RAID and want to - http://www.thegeekstuff.com/2010/08/raid-levels-tutorial/


awdj said:
I agree, as long as he keeps a backup of the entire array, preferably off-site. And I mean that for -any- RAID level. Although I wouldn't entirely dismiss RAID10 -- it is definitely more robust and less complicated (as far as how your data is stored.)
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Stepping back, we're discussing 3 separate topics here - storage space (and options), backup and disaster recovery.

Storage space - I have nothing against any RAID level. They all have advantages .. all comes down to cost and use. How much do you want to spend and how much space do you want? The cost usually dictates how much space you will have .. and the technologies used.

Backups - I totally agree about the backups .. and no business should be without this at any level, RAID or no RAID. Home use, sometimes things change a little - usually because of funding, sometimes because they don't know and some don't care until they have lost data. To most home users, it's not even a thought.

Disaster Recovery - With 'off site' specifically, you're stepping more into the realm of disaster recovery (recovery in the event of total loss). For the typical consumer and quite a few small businesses, it gets complicated when you start talking about this - usually because of the additional requirements and funding. To some, this is even less of a thought .. also when it's too late.
 
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As awdj and ittigger pointed out, it's always a good idea to back up your data. I have several copies of my music library, and at least one copy of my data on other computers, servers, NAS's, or portable hard drives in my house, but they wouldn't do me much good if my house burned down. I have a portable drive with my music library on it handy, which I kept with me in the event of a tornado warning, however, that was only a portion of the irreplaceable data I have.

I was in the IT business for about 43 years before I retired and I developed and documented numerous Disaster Recovery plans during that time. I knew what I needed to do, but always seemed to find something more important to do. Finally, after participating in this thread, I decided to do something about it.

I was building a new computer, so I ordered an extra 2.5 inch, 2TB drive and a portable enclosure, and I backed up all my data; including my music library, e-mail, and software licenses, and stored it in my safety deposit box at my bank. It gave me the opportunity to take some important papers with me and put them in the safety deposit box as well. In the next month or so, I'll get a second drive so I can routinely rotate the drives (maybe monthly) in order to keep the backup fairly current. It cost me less than $100 and a few hours of my time. I feel a sense of relief, now that I've done what I should have done years ago. Thanks awdj and ittigger!:)
 
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Got the drives in .. decided to stick with RAID 1 .. so I have 2 volumes .. a 2Tb one and a 3Tb one .. each mirrored.

Going to start moving files to it this weekend. I'm hoping the 3Tb one has enough space to handle my media (movie, music, pictures) and I'll use the 2Tb for our laptop/desktop backups.

Once I sort things out, I'll move my 4Tb drive to the NAS and back it up to the 4Tb and keep it offsite.
 
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steve149 said:
Got the drives in .. decided to stick with RAID 1 .. so I have 2 volumes .. a 2Tb one and a 3Tb one .. each mirrored.

Going to start moving files to it this weekend. I'm hoping the 3Tb one has enough space to handle my media (movie, music, pictures) and I'll use the 2Tb for our laptop/desktop backups.

Once I sort things out, I'll move my 4Tb drive to the NAS and back it up to the 4Tb and keep it offsite.
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That will work. I kinda thought the two volumes was the way you would have to go to get the full benefits of your different size drives. It sounds like you figured out how to balance out their utilization. Good job!


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