External Storage questions

[we3fan]

Hi guys,

I have 3 TB of data that I want to back up on 2-3 Hard Disks externally and make 2-3 copies of the same data on separate Hard Discs.

So basically I plan to buy 2-3 (maybe 4 eventually) internal Hard Disks and put them in External Enclosure with 2 or 4 bays, so I can put minimum 2 and maximum up to 4 Hard Discs in the External Enclosure.

1. Do you guys think that 2 bay External Enclosure with 2 Hard Disks inside, both Hard Discs containing the same data, is reliable enough for backup?

2. Or I should buy a 4 bay External Enclosure with 4 Hard Disks inside, all 4 Hard Discs containing the same data, making it even more reliable?
I don't know if this is possible, and probably has an extremely small chance of happening, but what if something happens (electric shock maybe) to my 4 bay enclosure and all 4 Hard Discs inside stop working at the same time?

3. Or I should buy 2 External Enclosures with 2 bays and put 2 Hard Disks in both and end up with having a total of 4 Hard Discs in 2 separate External Enclosures with 2 bays?

4. At first I wanted a smaller External Enclosure only for 2.5" Hard Discs so it will take less space, but right now the maximum is 2 TB for 2.5" 9.5 mm Hard Discs, so I guess I have to also buy a 3.5" Hard Discs with bigger capacity than 2 TB, do you guys think it is safe to mix 2.5" and 3.5" Hard Discs inside the External Enclosure?


Now let's see what kind of External Enclosure to buy:

a. I don't want RAID features because that is more expensive and I can manually make sure that the data on each Hard Disk is identical, but if it is a really good External Enclosure and it comes with RAID I guess I could still consider buying it.
I think I read somewhere that if you accidently press the 1/0 RAID switch that is usually at the back of the External Enclosure it could potentially corrupt your data, I could be wrong about this because I have never used RAID before.

b. External Enclosure with metal trays inside with screws to tighten the Hard Discs as tight and steady as possible, so there is less vibration; I don't mind a little extra work and screwing a few screws when putting the Hard Disc inside for the first time if that is going to extend the life of the Hard Disc.

c. Right now I have a laptop with 4 USB 2.0 ports, so I guess an External Enclosure with USB 3.0 would be a good option, I don't want it to be ultra fast like Thunderbolt because that is more expensive.


Thanks for your time guys, I hope you can tell me some recommendations for a good external storage.

[day1data]

Buy a 2 bay NAS to backup to (Synology are pretty rock solid) and setup both drives in RAID 1 (Mirror). I have found if drives are in a NAS you are much more likely to be warned of a SMART error and have time to replace the bad drive than managing single external drives that have no redundancy. But that's just my opinion.

Then if your paranoid buy an external drive and set the NAS to backup to it like once a day.

[LarrySabo]

Connecting a multi-bay enclosure via eSATA requires a motherboard that incorporates an eSATA port multiplier. eSATA port multiplier cards are expensive, especially when you get up to many ports. Forget USB 2.0; USB 3.0 automatically incorporates port multiplexing so a multi-bay USB 3.0 enclosure may work but it won't have automatic redundancy.

I would suggest a 2-bay enclosure set for RAID 1 plus another as a back-up of the first. QNap and Synology are leaders to consider and some models incorporate features to upload a back-up to an off-site repository. I would also recommend a UPS for the RAID enclosures and your computer system to reduce the risk of electrical events frying your devices. Staying away for 3T Seagate drives is probably the most important step.

Finally, also look into ShadowExplorer, which can provide automatic backup to other computers on your network, as well as storage enclosures.

[we3fan]

Thanks for the advices so far guys, I am a beginner at external HD storage and still learning many things and your advices are more than welcome.

I have a few more questions to help me understand how these things work.

5a. I have a question about the RAID system in different external enclosures, is the RAID system built and work in the same way (the hardware or software included in making it) and can be equally reliable in different external enclosures with different prices and brands?

5b. Will the RAID system in an expensive external enclosure be more reliable than the RAID system in a cheap external enclosure?

5c. Is it possible sometime only the RAID system to fail and stop working but all the other components inside the external enclosure to work OK?

Dialogue example:
"My external encosure is not working anymore, I need to buy another one"
- "What happened? Was it the fan? The power adapter? The cables?"
- "No, all is working fine, just the RAID got corrupted somehow and doesn't work properly anymore"
Is such thing possible to happen?

6. I have a question about RAID 1, if I have 2 HDs that are half full with data, and I put both my HDs in an external enclosure with RAID 1, will both HDs be erased and all the existing data on both HDs will be lost?

7. Let's say I have 2 HDs in a RAID 1 external enclosure that are half full with same data and all is working good, after some time the external enclosure fails somehow and I need to buy another one, what will happen to both HDs when I put them in a new RAID 1 external enclosure?
Will all the data on both HDs be erased again?
Is there a way for the new RAID 1 external enclosure to recognize that both HDs have been in RAID 1 before and have the same data and continue to work normally without erasing all the data again on both HDs?

I really appreciate your advices to buy NAS, and my 2nd external enclosure will probably be a NAS because I also read that NAS is great for external storage, but because I will be using my old laptop, which has been great for 5-6 years now and has only USB 2.0 ports, for 1-2 more years, I think I will buy a cheaper external enclosure the 1st time to get a good feel how all this works before I replace my old laptop with a new PC that has USB 3.0 or eSATA ports.

So right now I have only USB 2.0 ports on my laptop so even if I buy a USB 3.0 external enclosure I can't use the USB 3.0 speed for the next 1-2 years until I buy a new PC with USB 3.0 ports.

8. I see that many external enclosures have HD LED lights, will all these HD LED lights warn you with SMART error before the HD fails? Or only NAS external enclosures have the ability to warn you with a SMART error before the HD totally fails?
Will the HD LED lights in many average external enclosures warn you with SMART error before the HD fails? Or they will only light red color when the HD has totally failed and is already too late?

[we3fan]

Hi guys,

I wrote a long reply, like in my 1st post with a few more questions, but when I try to post it, it says: the post needs to be approved by moderator.

I don't know how long this approval might take so I wanted to contact some of the admins here, but I could't find out how to send them a PM about it.

I am sorry for posting this here but I just didn't know what to do to get my full text posted here.

I hope some of the moderators will see this and guide me in the right direction.

[SOSdonnees]

I have 3 TB of data that I want to back up on 2-3 Hard Disks externally and make 2-3 copies of the same data on separate Hard Discs.

First, I would suggest avoiding drives over 2 TB, because if some day a problem occurs, some data recovery softwares that are designed for 32-bit systems cannot handle drives of more than 2 TB.

If you can, buy drives from 1 TB or even smaller.
Today, you can find for very cheap 500 GB drives on the second hand market.
If you need a lot of security, buy more small drives with the same money that you would spend for large drives. Dont' put all your data in the same bag.
With tools like HDSentinel or HDTune, you can check that second hand drives are in good condition.

If it is for backup purposes (i.e. you also keep the data on the original drive), you could use single-drive enclosures, copy the content twice and store it at different locations.

With RAID-1, the same content will be duplicated on both drives.
This is a further security.
However, keep in mind two important things :
1. Many RAID systems are using Linux file systems like ext3.
If you delete a file accidentally, its name will be lost (because of the nature of the ext3 file system).
So, if you're including the risk of human errors, you should better use a classical SATA enclosure for one drive, formatted in NTFS.
2. Be careful with RAID systems that are sold with the drives inside as the (hidden) drives that inside are often low cost (unreliable) ones.

Further considerations:
- 3.5'' drives are in general more reliable than 2.5'' ones
- 3.5'' drives are easier to repair than 2.5'' ones (especially for the circuit board)
- Amongst the 3.5'' drives are consumer or enterprise grades.
The enterprise grade series are more reliable than the consumer grade,
not necessarily for the PCB, but concerning the internals (mechanical design).
The price of an enterprise drive is typically about 150%-200% of a consumer drive.
- Enterprise grade series are for instance:
Hitachi Ultrastar, Western Digital Re or Se, Seagate Constellation
- If the drives are in a RAID, take a drive which was mechanically designed to support the vibration caused by the RAID (for instance Western Digital Re series).
- Avoid RAID-5 : as it makes the data recoveries more complicated and as RAID-5 systems are often using ext3. Furthermore, in RAID-5 two drives may fail more or less at the same time, annihilating the "security" of RAID-5.

In summary
- Keep things simple as simple systems make data recoveries easier.
- Choose quality drives.
- Store your drives at different locations.
- And don't forget to backup on a regular basis.

[we3fan]

Reply from LarrySabo:
"Connecting a multi-bay enclosure via eSATA requires a motherboard that incorporates an eSATA port multiplier. eSATA port multiplier cards are expensive, especially when you get up to many ports. Forget USB 2.0; USB 3.0 automatically incorporates port multiplexing so a multi-bay USB 3.0 enclosure may work but it won't have automatic redundancy."
9. Does that mean that if I connect a 2 bay external enclosure on my old laptop's USB 2.0 port it will not warn me before a HD fail happens?
It still can't warn me even If I had USB 3.0 port on my laptop?
It can only warn me if I use eSATA?

10. I read somewhere that "desktop storage devices can also offer redundancy", does that mean that laptop 2.5" HDs don't offer redundancy?
Is SMART error detection built only in 3.5" desktop HDs?
Or SMART error detection is built in 2.5" laptop HDs also?

I plan to copy all my 3 TB data on a 2 bay external enclosure, and after I copy everything I plan to use the enclosure only 1-2 times a week for 1 hour to copy some files back to my laptop.
11. Is it better if I have the external enclosure powered ON and working all the time even when I am not copying files on my laptop so I can monitor the HD LED lights if something bad happens before a HD fails?
Or is it better if I turn ON the external enclosure 1 time a week for 1 hour, copy some files back to my laptop and turn OFF the external enclosure, and turn it ON again when needed?


Thanks again guys and sorry for the many questions.

[we3fan]

Thanks a lot SOSdonnees, great advices, I really appreciate it.

I decided to buy something cheaper the first time so I am thinking about these two external enclosures:

1. Ultra U12-42069 USB 2.0 Dual Bay External HD Enclosure
http://www.amazon.com/Ultra-USB-Dual-Ex ... B009A8ZID2

2. Rosewill Aluminum 3.5-Inch USB 2.0 DUAL BAY External Enclosure R2-JBOD Black
http://www.amazon.com/Rosewill-Aluminum ... B004AA0QO6

They have good reviews, has anyone of you guys had any experience with these external enclosures?

I want to put 2 HDs inside and use them as separate HDs (I don't want RAID for now), I hope I can do this with these 2 external enclosures.

I have an interesting question now, both of these external enclosures are supposed to stand vertically, but I prefer if they were designed to stand horizontally (HDs parallel to the ground), so I intend to use them in a horizontal position (HDs parallel to the ground).
Is there some negative effect if I use them positioned horizontally?
Or is it better if I use them positioned vertically as they were originally designed to be used?

I also intend to put one 2.5" HD in one of these 3.5" external enclosures just to try if it will work OK compared to the other 3.5" HDs.
I read somewhere that to use a 2.5" HD in a 3.5" external enclosure you must use a Disk Holder type C or some other type, so I guess I need to buy 1 of these Disk Holder types too if it's not possible to manually tighten and screw the 2.5" HD somehow in the 3.5" external enclosure.