Does it sound like it is at least spooling up and running? If you open Disk Utility, does it see the drive as mounted? Can you run diagnostics on it?
Any hard drive can fail, and few give any warning signs before they do, so the fact it was working fine and now is not does not tell you anything.
If disk utility cannot even see it at all, then you may have a failed drive. This is one of the reasons many of us advocate multiple redundant backup strategies.
Thanks, Michael! I do hear it at times spooling up and running. Just after I bumped the thread I looked for troubleshooting for this drive online and found the manual which suggested using Disk Utility which I've seen before accidentally (if I hit Command Shift U instead of Shift U to type "Unit" on a new folder for a student's homework ) but had never really noticed. Disk Utility does see it and also a sub-something (directory?) which might be the Time Machine archives on the disk, called disk1s2), sort of the way that my iMac's hard drive shows up as 640.14 GB Nitachi HDT7... and has a sub-something titled DB iMac, which is what I named my iMac's hard drive.
Anyway the owner's manual just shows the image under the formatting section, not the troubleshooting section, but as soon as I saw it in the manual I remembered seeing it accidentally a few times, went to it, and am now verifying the disk. Right now it's telling me that it will take 2 hours to complete the verification, so I guess I have a bigt of a wait. :-)
Does that fact that Disk Utilities can see it mean it's not failed, or just that it hasn't completely failed?
I can see the virtue in having multiple redundant backups, or at least two backups. What do you suggest? Two external hard drives? I had this one linked by ethernet, and but I also have a cord that could link it by USB (like a printer), so if this one is reparable I could get a second one and link it by USB. If this one is not reparable I could get two and do the same thing. I do have an Airport so I suppose it's possible to get some sort of Wi-Fi hard drive (my new printer/scanner uses only the network and not a cable, although it has a cable that I used for the initial installation), but I'd suspect a Wi-Fi hard drive might have a higher price.
What hard drives, if any, do you recommend? I seem to recall that when I was looking at external hard drives 4 years ago, Apple's were substantially more expensive, which is why I got the OWC Mercury Elite All Pro.
I think the OWC drives are great drive (I have a few myself), but again, any hard drive can fail - there simply is no such thing as a failure proof hard drive or SSD drive for that matter.
A drive can fail for two reasons - a mechanical failure, or a logical failure. If it is spooling up and running, then that would indicate it is likely not an outright disasterous mechanical failure.
Let DU do its thing and see what it says - it may be a recoverable logical error, which do have a tendancy to become more likely with time/age of a device.
BTW, the two entries you see in DU are 1) the physical volume, and then 2) the logical volume. So "disk1s2" is the physical volume/device, and then Time Machine or whatever would be the formatted logical volume created on that physical device.
My own backup strategy is to use a TM volume - mine is a WD MyBook 1TB USB2 drive of about the same vintage as your OWC drive - and then I have two portable bus-powered drives for full bootable system clones (made with the shareware CarbonCopyCloner from Bombich software). One is a USB2 bus-powered WD portable drive, and the other is a SeaGate FireWire 800 bus-powered portable drive (that one lives in the fire safe inbetween weekly incremental clones). I have a 1TB OWC mercury elite pro firewire 800 drive for just extra external disc storage.
Redundancy is really the only solution to safeguard against any one drive failing (BTW, all of my backup drives are at least 4+ years old now, as I got them all new once I got my MBP back in March 2009). I have known hard drives that have failed within hours of opening the packaging and installing the drive, and others that have lasted far beyond anyone's wildest guesses of effective lifespan (I have one drive in a 486Sx laptop from 1997 or thereabouts that still runs just fine).
Is the drive the Mercury Elite Pro that takes 3.5 inch drives, or the Elite Pro Mini that takes smaller 2.5" laptop drives? If the "mini" and you are connected by USB, the drive motor may now be demanding more power than a USB port alone can provide. Many electric motors start to need more power as they age.
Solutions outside of replacing the drive (if you have the Elite Mini):
1) If it's not already, reformat the external with Disk Utility so it is formatted Mac Extended (Journaled). That has helped in some instances.
2) If it is the "Mini" buy the optional external power supply:
3) Get a powered USB hub to put between the computer and the drive
4) Get a "Y" USB cable to tap the power of two USB ports"
Above all, if the drive has FireWire (many OWC models do) by all means use it. It is more reliable and faster than USB.
An hour later and it's still estimating two hours to completion of the verification. It's like the man who can never cross the road because he keeps only cutting the remaining distance in half. :-D
I don't know some of there terminology. What is an SSD drive? How about a TM volumne? I got my physical owner's manual and my external hard drive is an OWC Mercury Elite-AL Pro "Quad Interface" eSATA/FireWire 800, FireWire 400 & USB2.0 Combo Solution. It's actually different than the one for which I found instructions online.
What is a a USB2 bus-powered WD portable drive? What is an MPB?
I'm sorry, but I don't know what you mean by "takes." That conjures up images of the old floppy disks, but I suspect that's not the sort of thing you mean. It's just a box I plug into the computer. I'm using a FireWire 800 cable. I got my physical owner's manual and my external hard drive is an OWC Mercury Elite-AL Pro Quad Interface" eSATA/FireWire 800, FireWire 400 & USB2.0 Combo Solution. So I'm guessing it's whatever you mean by a 3.5-inch drive. It's not the same as the mini in any case, which I see online doesn't have the FireWire 400 port, has the power plug in a different location, and has a different on-off switch. From the phoot too it looks like its casing might be both wider and shorter than the casing of the one I have.
Right now I'm going a Disk Utility verification. I don't want to reformat it if I can fix it with the Disk Utility.
I had this one linked by ethernet, and but I also have a cord that could link it by USB (like a printer), so if this one is reparable I could get a second one and link it by USB
The drive should have come with USB and Firewire cables - Firewire being the fastest connection; everything else will take much longer. I don't believe this drive has an ethernet port. So which are you using currently?
Edit: I see you posted in the meantime saying you're using Firewire.
What is a a USB2 bus-powered WD portable drive
That means it draws all its power from the USB ports; it is better to have one that is plugged into the wall.
An MBP is a Macbook Pro.
If that drive is near full, or if there are errors it is finding (and hopefully fixing) it could take awhile.
SSD = solid state drive, basically a drive made from non-volatile RAM chips (RAM that does not loose its content when the power goes off). Basically the same stuff as in a USB thumb drive, just scaled up to equal the capacity of a hard drive. SSD's are much faster than mechanical hard drives, but actually no more reliable overall (although they can be more easily ruggidized against shock and moisture damage - the military has been using them in field equipment for much longer than most consumer grade equipment has).
TM = Time Machine - people here tend to abbreviate it rather than type the full thing every time.
A bus-power drive is one designed to run off just the power available through the interface port. Firewire, USB and lightening ports actually supply some (limited) power, but enough that in a properly designed device, they can be powered completely over the bus connection itself (no need for an external power supply). Some shoddy USB devices do not conform though, to the industry standards for USB power, and will not actually work without an extra power supply. These do save needed to plug them into the wall socket though. I've used several WD bus powered portable drive for years with my Macs and never had an issue with them (same for my little SeaGate Firewire powered drive), but these drives are just plugged in periodically to update their clones, then put back away. They are not as robust for normal, regular drive use as an externally powered device.
Sorry. I meant FireWire 800. My buddy who's a computer programmer mentioned ethernet last night and on only 4 hours of sleep it stuck in myhead.
The OWC does have an external power source. I just saw a new OWC at http://eshop.macsales.com/item/Other%20World%20Computing/MSU35S1.5T32/ that's bus-powered and figured out what "bus-powered" means. :-D
I think I'd rather have the external power source so that I don't have to worry about what Allan mentioned above. I want to take care of this and have it done this week, not be hassling with it for weeks.
Is an SSD any better than a standard hard drive?
Is WD a brand? I've seen a couple online, including this one: http://www.jr.com/wd/pe/WD_BY8L0015BBK/. Oh, the WD looks like a brand logo, so I think I answered that question myself too. :-P
Oh, what's the bit about clones? Is that an old reference to non-IBM PCs (which we used to call clones at least back in the DOS days) or to something Mac-relevant?
WD = Western Digital, so a brand name. I've had good luck with their drives, but also Seagate and OWC.
Personally, I would not want an SSD for a dedicated backup drive. Yes they are faster, but in many ways, a conventional drive is more reliable over the very long haul. With TM, the initial backup can be slow, but after that, the incremental backups are quick, so drive speed is not so critical to my mind. Plus you can get so much more capacity for much less money with a conventional drive versus an SSD and that is more important than speed in terms of a TM drive, to my mind.
A bootable disk clone is just that - a complete, independent and bootable copy of your entire boot drive. A clone can be plugged in and used to boot your system, and will work just as if you had booted from your internal drive. It is a superb backup method to have both an emergency boot drive available (you can boot from it if your internal drive fails), as well as to have the ability to readily re-clone your system to a new internal drive.
TM is great for restoring individual files or folders as needed, but it is not bootable and is more cumbersome if trying to fully restore you system from scratch. So, my opinion is that a TM and a clone or two give you the greatest flexibility in backup & recovery, no matter what happens or how extensive a recovery you need to implement.
It looks like the progress bar on the verification is stuck. Underneath the progress bar is a line of text that says,
"Total Capacity : 1.5 TB (1,500,301,910,016 Bytes)" and the progress bar is stuck above the 1 in 301. I'm going to try to get a 90-minute nap before I have to be in the tutoring center at my university center all night, and I'll leave the verification running, but I have a bad feeling it's not going to make any more progress. If it doesn't make any more progress, does that mean likely that the disk is damaged? Can I try repairing the disk using Desk Utility without first completing the verification?
Oh, I just noticed under the Show Details, in the big box, there do appear to perhaps be more lines than before:
Verifying volume “disk1s2”
Checking multi-linked files.Checking Journaled HFS Plus volume.
Checking extents overflow file.
Checking catalog file.Perhaps the bar will stay stuck at its current progress level until it finishes scanning all the multi-linked files (whatever those are)?