Internal Time Machine "looking for backup disk" (not time capsule)

Nobody?

I disabled TM, deleted the TM pref file, reformatted the TM drive completely (losing all my old backups!), rebooted, and tried activating TM again.

"Looking for backup disk..."

This is getting ridiculous. TM always worked perfectly for me, for years, until now. It has been working perfectly on this BRAND NEW internal drive for many weeks. And now... I can't get it to work at all!

😟

I considerd it, but I am very reluctant to do so as I was sure it had to be some small issue somewhere. Completely re-writing OS X seemed like a heavy-handed solution.

I think I figured it out though! I booted into safe mode and it worked. AHA! One thing that safe mode does is restrict the kext loadup. I used Kext Wizard to export a list of all loaded kexts for both normal boot and safe boot, then cross-compared to obtain an "unsafe" list of about 20 kexts. Most were innocuous, but I noticed that the NTFS and FAT filesystem kexts fall into that category. BINGO! My most recent activities include a new internal drive and some other partitions for Windows 7. Clearly, the OS X filesystem kexts were not playing nice with some or all of those partitions, even when they were not mounted (crazy!). So I booted back into safe mode and tested a bit. Yep, if I unloaded the filesystem kexts, Time Machine worked perfectly. Now I'm in the process of finding out which partition/filesystem is the culprit; I am hoping that it turns out to be the FAT partition I made, as that one is empty and not strictly necessary (I was using it as a fast internal swap directory, but it's empty at the moment).

For those who have no idea what I'm talking about, OS X stores two kernel extensions (msdosfs.kext and ntfs.kext) in /System/Library/Extensions (root library, not user library). These allow OS X to R/W to FAT16/32 volumes and to read NTFS volumes. If you have this error of "looking for backup disk" on a system with such volumes attached externally, try disconnecting them and trying again. If you have this error on a system with internal partitions, merely unmounting the volumes does not seem to help, you have to prevent the kext from loading in the first place. I will post back with any more info I can get.

Turned out one specific NTFS partition was the culprit. It was a backup partition, being written to an internal drive that was ALSO a content drive (non-boot) for OS X (included in the TM backup), and had been formatted from Windows. For whatever reason, Time Machine *really* didn't like that. So I deleted it; I use Windows for games ONLY, and my game saves are backed up in Steam anyway. Plus I have a weekly offsite clone drive for Windows.

My OS X backup solution is multipartite. An internal time machine backup lets me keep local previous versions of ALL files, not just documents programmed for it. It also provides me with a potential restore point.

A second internal drive contains a nightly bootable clone. So I can boot up right away if anything goes wrong, and I have that much more data redundancy.

Finally, an offsite clone, kept in another state and updated weekly, provides disaster recovery in the case of fire/theft/etc.

That's on top of keeping all my important documents in iCloud/Dropbox, and backing up my Aperture and iTunes libraries once a month to separate external offsite drives besides.

I am, as you can guess, very concerned with preserving my data. ;-)

To be honest I don't even remember. In the past week (Win7 is a new install) I've tried something like 6-8 free backup programs, and each of them had a critical flaw of some kind in my view. So at the moment I am still researching what is going to end up being the route I take vis-à-vis Windows backups.

I tried:

Cobian - decent, but weak on the restore side (it just copies data over, there is no system restore feature)

Genie Timeline - looked nice, but when I saw there was no backup of system files I didn't even run it

Paragon - pretty good, but for some reason or another I kept looking (I forget why, I'd have to launch it again to remember... I should have taken notes)

Macrium Reflect - very close, but the free version didn't have incremental backups! :-/ It also didn't support GPT disks, which meant I couldn't write to my internal drive for redundancy.

Backup Maker - not as good as Cobian, similar ethos (just copies data, doesn't do drive images or system backup).

Some others too. I think Macrium was probably the closest to serving my needs, but the lack of incremental backups was annoying.

Chemec,

Based on your description, it sounds like disconnecting the SD drive, or even booting without it connected, is a good idea to at least try. If TM works without the SD reader attached, then you've at least narrowed down the issue.

I don't know how to tell what TM is doing under the hood, or where it hangs; perhaps there is a console log for TM that goes into more depth, but that's beyond my knowledge. I only figured out which kext was causing problems for me by cross-comparing which kexts were loading in normal (not safe) boot with my own knowledge of recent changes to my computer. Knowing I had recently set up FAT / NTFS drives, and seeing that there are NTFS / FAT kexts, I then made the step of (carefully!) removing those kexts (temporarily!) to confirm the issue.

So again, my first suggestion would be to remove the SD reader, reboot, and see if TM works. If not, try unmounting drives bit by bit. If that doesn't work, you can try removing the NTFS / FAT kexts altogether from your system and see if that works (keep a backup though so you can restore them!).

At least at that point you'll know if our problems are comparable. If not, good luck! It's a maddening error, that's for sure.

[Just a note, TM only works on OS X Journaled drives (i.e. HFS+ drives). TM does not back up your FAT drive.]

Isaac:

If you unloaded the NTFS and FAT kexts, your TM backups might (might!) work again, but of course in that case you would not be able to see your FAT or NTFS drives in OS X, and if you removed the FAT kext then a lot of USB keys would be unreadable in OS X - not a good solution.

The kexts are specific to OS X, so removing them should not affect Windows... but may affect boot camp, I don't know how boot camp is programmed (which would be a problem). Luckily if your Windows drive became inaccessable from boot camp with removed kexts, it should be easy enough to simply boot back into OS X, restore the kexts, and then Windows should work again.

I would recommend not mixing partition types on drives with shared OSX/Win functions, it seems to "tempt fate" as it were with possible errors. I don't know what has precipitated this error in your case, if it was the MSE or disk error or something else, and unfortunately I don't have a real fix to offer beyond trying things with the kexts removed and seeing if they work.

NOTE THAT THIS IS AT YOUR OWN RISK, messing with kexts is not a very recommendable practice since these files enable core functionality in the OS. Make a backup before if you can, and consider your options carefully. In OS X, navigate to /System/Library/Extensions and you'll find a bunch kext files. The two you need are msdosfs.kext and ntfs.kext. Copy ntfs.kext into a backup folder (e.g., on your desktop). Delete the original ntfs.kext from the S/L/E folder. Reboot and see if you can still access windows. If so, reboot into OS X and see if Time Machine works again. If you're good on both those points, then consider going without ntfs.kext on a permanent basis – it is rare that you need to read an NTFS drive while in OS X. On the other hand, if this does not fix your problem, you may try restoring ntfs.kext, and backing up / deleting msdosfs.kext to see if THAT is the culprit. Unfortunately, if msdosfs.kext is causing the TM error, you're kind of out of luck, since going without FAT access will be pretty annoying any time you need to use a drive to swap files between Windows and Mac (using a USB key).

Ultimately I don't have a solution, as I have noted, so much as I've narrowed down where the error is occuring in some peoples' cases (like my own). Good luck!