"Time Machine completed a verification of your backups."

Hi Starwarrior,

you may need to read up a bit on some technicalitites in order to make use from these posts.

This is easy enough to do by using Google and Wikipedia, etc.

But to cut to the chase:

TimeMachine stores your backups in a specific disk image format that can grow when the contents increases.

This specific disk image format is called a "sparsebundle".

When you double-click on such a disk image, it gets mounted in the finder just like any other disk image or drive.

Alternatively, you can mount such an image using "Disk Utility" or by control-clicking on it an chosing the appropriate command.

Christof Birkenmaier wrote:

. . .

TimeMachine stores your backups in a specific disk image format that can grow when the contents increases.

This specific disk image format is called a "sparsebundle".

That's used only for backups done over a network. Backups made to an internal or directly-connected external HD are stored in a normal folder named Backups.backudb at the top level of the drive. For network backups, that folder is at the top level of the sparse bundle disk image.

Thanks Christof that is helpful for us novice star warriors who don't have a clue how things work.

Now is there a simple explanation for the common steps to take to avoid having to be asked by TM to do a new back-up, because the verification failed and thinks the current back-up is unusable, or are we now saying the best process is to basically fix the file when it goes bad by doing all those steps I didn't really understand.

Thanks Pondini! I checked on one of my wired disks and it's exactly as you say. Since I only ever had this problem with my TM backup on a NAS on WLAN, I had only looked at those.

Hi Hansolo!

When these things happened to me for the first time, I researched a lot and in the end I found no plausible explanation as to why.

Some people suggested that it may have to do with the name of the machine, the hard drive or the network drive (NAS).

My machine's name for example contains an apostroph.

However, this never really made much sense to me, since many backups just simply work and if it were to be a fundamental error based on the machine name, it should fail every time.

Since my NAS (a Synology DS 210j) is set to automatically shutdown at a given time in order to conserve energy, another suspicion is that maybe the backup gets corrupted when the NAS accidentally disconnects while TM is writing stuff to it.

But no certain explanations.

Sorry!

but to fully answer your question:

I do not know of a way to prevent it from happening and I believe that unless you are terminal savvy (which I am not) and can follow for example Garth's tutorial (http://www.garth.org/archives/2011,08,27,169,fix-time-machine-sparsebundle-nas-b ased-backup-errors.html) mine is probably the easiest way to do it - sorry!

Christof Birkenmaier wrote:

. . .

My machine's name for example contains an apostroph.

That did cause problems in early versions of TM (fixed by the time of Snow Leopard, as I recall). Odd characters, and names over 25 characters long can still cause intermittent problems (although that seems less frequent in later versions of OSX). See #C9 in Time Machine - Troubleshooting

Since my NAS (a Synology DS 210j) is set to automatically shutdown at a given time in order to conserve energy, another suspicion is that maybe the backup gets corrupted when the NAS accidentally disconnects while TM is writing stuff to it.

That's a real possibility, especially if it doesn't notify OSX properly and/or doesn't do OSX journalling properly. (I don't know the gory details, but as I understand it, the journal is supposed to be forced to hard disk before the actual data is even queued, so if there's an interruption, preventing the data from being written completely, OSX can "back out" the partial data when it reconnects.)

Hi hoppah,

could you please explain to me what a RAID scrub is and how I can find out whether my NAS (Synology DiskStation 201j) is doing one?

Thanks!

Christof

Thanks a lot! Took *forever* but it worked exactly as Christof notes above. TM is now running as usual, and I was able to reach back to April 9th and pull a file that I'd deleted off my desktop.

More details: TM backups failed last Wednesday with the error noted in this thread. BTW, it took about 2 days to mount a 1TB sparsebundle (have my TM backup on a Synology DS411 NAS). If you're trying this with a large TM, be prepared to wait a loooong time for each function you request. Fortunately everything can be done in the background without beachballing your other computing efforts.

Again, tons of thanks to Christof for detailing everything out so clearly here!

Christof, Pondini,

Thanks for trying to help. What I decided to do is to do another back-up using a land line and then to turn off time machine until such time as I am connected via land line. It only took about 4 days before it started asking to do another back-up. Granted that perhaps there is a problem with the land line too, but it seems like the program should not be so sensitive. I really can't continue to use the time machine program if these keeps happening. I had just updated my Mac to OS 10.7.4. Mine is a Macbook Pro 13" purchased less than a year ago. I had been doing back-ups across the WIFI network originally and originally the verifcation error would occur once every few months. Now it is happening every week, which is just too much for me to handle.

Can either of you give me a few of the common suggestions for what if anything I can do to try to stabilize the situation. I really can't do much more than turn it off and use it when it is just on a LAN conection and my impression is it failed more frequently not less with the LAN connection and with the latest LION update.

I'm about to give up on the back-ups altogether as this is not very helpful to me.

Han

I forgot to add that I am using a Seagate network drive with their GOFLEX software.

Han

hansolo415 wrote:

. . .

I really can't do much more than turn it off and use it when it is just on a LAN conection and my impression is it failed more frequently not less with the LAN connection and with the latest LION update.

Do you mean Ethernet vs. WiFi? Technically, both are your network.

The only things I know of are in the green pink box in #C13 of Time Machine - Troubleshooting.

Message was edited by: Pondini

hansolo415 wrote:

I forgot to add that I am using a Seagate network drive with their GOFLEX software.

What is that software? If you're using Time Machine, you most likely don't need it. Sometimes, software supplied with a drive isn't compatible with the latest version of OSX, and can interfere with it. WD Smartware (at least some versions) for example, can prevent Time Machine from accessing network backups!