2,5" external drive for backup of NAS?

[Griffon]

Hello,

Last year around this time I had asked here for some advice regarding my "first NAS" - I have been using a WD Live and I'm mostly happy, but I'm interested in getting a more advanced one (now that I have a "smart" TV, Airplay-connected sound system and can get a higher internet upload speed, to better use a "personal cloud").

I plan to get a Synology DS213/214 or a Qnap TS-220. I will back it up regularly to a USB drive, and until I get the NAS I will use it to back up my Mac mini (the WD Live is terrible for Time Machine).

I am thinking of getting a 2 TB WD Passport for this. The reasons are:

- I don't think I will need more than 2 TB; at the moment I'm not using more than 500 GB
- I would rather not worry about an extra power adapter and mains connection
- I can take the 2,5" NAS backup away for off-site storage, or rotate it with another 2,5" drive
- When I get a UPS that can shut down the NAS, the NAS will also shut down the 2,5" drive connected to it gracefully.

The only downsides I can think of are storage size (2 TB is enough for me), price (only 30 $ or so higher in Turkey) and MAYBE the USB drive drawing its power from the NAS could speed up its fan. I'd really want it to be quiet, I will be sleeping in the same room.

So, do you think it's reasonable to use a 2,5" USB drive to back up a NAS (or a Mac mini, until I get the NAS) or should I stick to 3,5" externals?

Thanks in advance!

 

[stevech]

2.5 in. if 7200 RPM (not 5400) and try for USB3.
But 2.5 in. cost more than 3.5 in. ($/GB). Especially at 2TB and up.
I'd get at least 2TB, 3.5in. USB3 or eSATA.
USB2 is a real drag for backups of NAS.

I use a 3.5in 2TB to backup my DS212, but only backup folders that are important, e.g., I don't backup drive image backups stored on the NAS, and the time backup on my NAS (which is on a separate drive #2).

I use ext4 format on that drive so it'll write a LOT faster than if NTFS format. I have a freeware program for Windows that will mount/read the ext4 drive, in an emergency such as if the NAS mainboard smokes. That program can also read the NAS internal drives since I use two volumes, one per drive, and I don't use RAID as for me, it makes no sense in a 2 drive NAS.

 

[Griffon]

Dear stevech, thank you for the reply. Your replies are always a big help for me - both when I was asking a year ago, and also now. I have also read your messages on the benefits of having 2 separate drives/volumes and I agree it's a good idea.

The 2,5" drives I'm considering (WD Passport 2 TB) have USB 3.0; they are 5.400 rpm but can read/write at 90 MB/sec (from online reviews). I don't think they are going to be a bottleneck.

The main reason I'm considering 2,5" drives is that I won't need a separate power connection, I can carry them easily for off-site storage, I don't need more than 2 TB, the price differential is not so much (in Turkey, for WD MyBook/Passport it's 150 $ vs. 180 $) and if the NAS is connected to UPS it can gracefully shut down the 2,5" drives - with a 3,5" drive powered directly from the UPS, it would just "uncleanly" shut down when the power goes off.

By the way, here's what I plan to do: Get 2x 3 TB drives, one of them is the "main drive" with a 1 TB volume for Mac Time Machine and the remaining as the "main storage" volume for photo, music, video, documents. The other 3 TB disc will be a Time Backup (done by the NAS) of the "main storage" volume, and the external 2 TB drive also backs up the "main storage". This way I have redundant copies of the "main storage" and don't repeatedly back up the Mac Time Machine backups.

Another way (simpler?) would be to arrange in RAID 1, allocate 1 TB for Mac Time Machine, the remainder will be "main storage", and the NAS uses the 2 TB external for "NAS Time Backup". But this way I don't think I can separately access drives in case of NAS failure, as you can.

So, at the moment I'm trying to decide between a 2,5" or 3,5" external drive, and I think you can see I want to go with 2,5". I was just wondering if it's generally a bad idea to go with 2,5" for NAS backup (maybe drawing the drive's power from the NAS increases the NAS' fan speed?).

Thanks again, and I hope some other members also chime in!

 

[stevech]

I would not rely on the 500mA (best case) from a USB source to reliably run these drives. I've had a lot of trouble with the drive not spinning up due to the motor startup surge, on USB power sources, and even on some cheap wall-wart transformer/power.

 

[Griffon]

But doesn't that make every 2,5" external drive "unreliable"?

 

[Griffon]

Perhaps this can be a solution: If I'm backing up my NAS to a USB 3,5" drive, and both are powered from the same UPS.. When the home electricity goes off, and the UPS tells the NAS that it has low battery left; can the NAS safely disconnect/power off the USB 3,5" drive, so that when the UPS runs out of power and the USB 3,5" drive suddenly shuts down, there will be no data loss/corruption on the USB drive?

 

[jlake]

Perhaps this can be a solution: If I'm backing up my NAS to a USB 3,5" drive, and both are powered from the same UPS.. When the home electricity goes off, and the UPS tells the NAS that it has low battery left; can the NAS safely disconnect/power off the USB 3,5" drive, so that when the UPS runs out of power and the USB 3,5" drive suddenly shuts down, there will be no data loss/corruption on the USB drive?

I think you'll be fine using 2.5 inch drives.

 

[stevech]

But doesn't that make every 2,5" external drive "unreliable"?

No, just use an enclosure that has a power connector and wall transformer.

 

[Griffon]

jlake, thank you for the reply. I was also leaning towards a 2,5 solution, for ease of carrying off-site.

stevech, that's a good option too. Though the main reason I was thinking about a 2,5 drive was working without an adapter.

I think I will get a 2,5" external drive plus a "powered hub" which can supply the necessary power to get the drive spinning. When I carry the disk offsite, the other computer's USB port should work well enough.

I will have around 2 TB for "main storage" (except Mac Time Machine backups) on the NAS, which will not be full for a long time; a 2 TB USB drive should do the trick.

Thank you for the comments!

 

[stevech]

I think I will get a 2,5" external drive plus a "powered hub" which can supply the necessary power to get the drive spinning. When I carry the disk offsite, the other computer's USB port should work well enough.
Thank you for the comments!

Powered hub might help, but the issue I've encountered many times is that the power (current/amps) needed for some drives to start-up is more than some/many USB ports can provide. Since the powered hub has a wall transformer, may as well use a 2.3 in. enclosure with a wall transformer and no hub. Or take a chance.

Backups are, IMO, too important to take risks.

 

[Griffon]

Well, I was planning to have placed the order for a 2,5" external until today evening, to be shipped during the weekend, but I couldn't. I'm not really sure about it now..

I would definitely enjoy not bothering with an adapter and even more power cables, and I could get another of the 2,5" drive later and rotate them, but now I'm worried if 3,5" might actually be a better choice. Mainly because of this amperage issue you have mentioned, and also if it would cause the NAS fans to speed up due to power consumption (I checked and the WD Passport draws 4 W at most - maybe this is too little to worry about?).

For the price of a 2 TB 2,5" USB 3.0 external, I can get a 3 TB 3,5" one. But this is kind of moot since ATM I don't have more than 500 GB to store.

Maybe I should ask some Synology (DS213 - DS213j - *maybe* DS214) owners if they ran into any problems with using a 2,5" external drive (powered directly from the NAS) for Time Backup. By the way: Do you think I would be better off skipping the DS213j in favor of a DS214se?

 

[stevech]

Well, I was planning to have placed the order for a 2,5" external until today evening, to be shipped during the weekend, but I couldn't. I'm not really sure about it now..

I would definitely enjoy not bothering with an adapter and even more power cables, and I could get another of the 2,5" drive later and rotate them, but now I'm worried if 3,5" might actually be a better choice. Mainly because of this amperage issue you have mentioned, and also if it would cause the NAS fans to speed up due to power consumption (I checked and the WD Passport draws 4 W at most - maybe this is too little to worry about?).

For the price of a 2 TB 2,5" USB 3.0 external, I can get a 3 TB 3,5" one. But this is kind of moot since ATM I don't have more than 500 GB to store.

Maybe I should ask some Synology (DS213 - DS213j - *maybe* DS214) owners if they ran into any problems with using a 2,5" external drive (powered directly from the NAS) for Time Backup. By the way: Do you think I would be better off skipping the DS213j in favor of a DS214se?

It won't affect the NAS' fans. But I'd not want to assume that the NAS has enough power for the 2.5 in. drive.

3.5 in. USB3 or eSATA. Not USB2. Cheaper too. But 2.5 in. with wall transformer would be a little bit easier to carry. Not much.

You could get a 2.5 in. SSD drive. Only 128GB is kinda affordable.