Ages ago I bought an Iomega ix2-200 two bay NAS with twin 2TB drives in RAID-1 mirror configuration.

A year or so ago I discovered that one drive had failed. I drove direct to a supplier and bought a 3TB drive of a comparable nature. Installed, and prayed to the gods of storage that the array rebuild completed before the second one failed. It did. Sweat wiped from brow, I enabled email warnings and went back to ignoring it.

Every time there's a power cut I get an email. That's all, so far. But hard disks being hard disks... one of them is bound to fail some time, likely the old original one now that they're mismatched.

Given how nervous a mirror setup makes me feel when one fails with no other backup... my plan is to add another 3TB drive to the array via USB.

My other plan is to replace the not-yet-failed 2TB drive with another 3TB drive and scale up the storage into the unused 1 gig.

My final plan is to extract all the info from my still-working USB 2TB drive and get that into the mirrored NAS storage.

That'll leave me with one happy external 2TB general purpose drive for moving big bits of data around, and one 3-way RAID-1 mirror NAS which I'm unlikely to be made nervous by.

Not a bad place to be. Unlike now.

A few things:

SSH is root@nas with password = soho+admin's password eg if admin has password 'p4ssw0rd' then it's 'sohop4ssw0rd'

Link to enable/disable that in the firmware I have is: http://nas/diagnostics.html

File systems are XFS inside LVM inside Linux SW RAID in mirrored mode. Root has ext2 mirrored FS for other stuff. Firmware lives on some flash on the main board.

Instructions: http://blog.millard.org/2011/04/non-des ... on-in.html

The 3TB drive in it is this: ST3000VX000 Seagate SV35 Drive 3TB 7200RPM SATA3
The 2TB drive in it is some low-end drive without the required reliability ratings! :-(

New drive to match: https://www.pbtech.co.nz/product/HDDSE6 ... D--durable

Although I don't care about speed much, I'm not sure it's a great idea to have a third drive over USB as it'll be quite a bit slower than the SATA inside, but perhaps not much slower than the LAN connection?

RAID info: http://www.tldp.org/HOWTO/Software-RAID-HOWTO.html and https://raid.wiki.kernel.org/index.php/Linux_Raid and https://help.ubuntu.com/community/Insta ... ftwareRAID

Considering buying some drives today... So:

Logistics:

2+3 raid with X data on it
2 usb with Y data on it
3 usb to buy
3 internal to buy mark drive as newer

Required steps:

T+ Backup all content to new 3 external
EZ Swap 2 to 3 internal - mark OK and keep old 2 as point-in-time backup with low reliability
T+ Rebuild Mirror to new 3 internal in 2 size - safe: 2 backups
EZ Resize md to 3 from 2 - care taken not to exceed byte count of any of the three drives - safe: 2 backups
T+ Add 3 ext to raid mirror set if possible - low risk, only one unreliable backup during this process, though
T^ Consolidate data from unduplicated 2 ext into new larger 3-way mirror raid array

Sleep easier.

EDIT: Ordered! Didn't really want to burn money on drives, but also don't want to lose data, and it's inevitable without proper precautions, so...

Some info:

Original purchase:

Order Number: 2012053116103714
Date Ordered: Thursday 31 May, 2012
1 x Iomega 35431 4TB ix2-200 StorCentre Cloud Edition NAS
Sub-Total : US$154.10
EMS Rates (Shipping to ES): US$36.50
Grand Total : US$190.60

So it's only 4.5 years old, actually! And the other drive died 2 years ago? Let's see if I can find a record of that... yep!

SV35 7200 RPM 3 year warranty
159+GST = 182.85nzd
6th of April 2015

So this is 1.5 years old, now! It was used the same day, however worth noting that the bad drive had failed possibly up to 6 months earlier.

And in a week or two or less the drives will arrive and I can begin the above process of ensuring I don't lose anything! About time, really.

Today's details:

Seagate SV35 Drive 3TB 7200RPM SATA3 HDD , durable reliability and performance tuned to the high-write workloads of today 24Hours&7days video surveillance systems ( 3 years warranty )
Part #: HDDSE6030 $163.00
Seagate 3TB Expansion Desktop
Part #: HDDSEA0433 $129.57
Total Delivery Cost: $5.00
Surcharge: $7.44
Sub Total: $305.01
GST: $45.76
Total: $350.77

The NAS didn't seen to recognise the USB drive, unfortunately. So I've plugged it into the new box as its first exercise in life and it's transferring over NFS to the USB drive. Four shares to do, starting with the biggest one, which was actually foolish, but whatever, the 1.5 year old drive is probably fine... :-/

This may represent a bit of a stuff up, though, as I may not be able to use it as the third part of a mirror. Hmmm. Still, I can get onto a fresher drive, and upgrade the size to 3TB. Then maybe just rsync the shares every once in a while. And plan to replace the older drive in a year or two, if it doesn't fail sooner.

When I plugged in the USB drive it didn't seem to show up anywhere, which was strange. I did an 'lsusb' but it reported "lsusb: cannot open "/var/lib/usbutils/usb.ids", No such file or directory" and just raw IDs. However I noticed that there were three. Just ran it again now and there were only two. Thus the USB WAS recognised, it's just a matter of finding the device or making it see the mass storage or something like that. And perhaps NTFS was an issue, too? No idea if you can format drives with the web interface, but hopefully not! :-D

I'm 3/4 through backing up the NAS to the new USB drive over wifi and rsync/cp with a few permissions fixups and other learnings/chores along the way. That should finish sometime today or tomorrow.

When I get home I can shut it down and install the new drive, let it sync, then try to resize it out to the full 3T size. Then I can have a crack at getting the USB 3T into the software RAID array as a third mirror. Wish me luck at this point :-)