TimeMachine "read-only"

A

aicul

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I am starting this thread because I have seen many people with similar issues on other sites and no real good solution proposed.

The problem relates to timemachine suddenly being unable to acces the backup disk (in my case timecapsule 1Gb) because the disk is apparently in read-only access.

Typically a message appears at each backup attempt that says "The backup disk is read only"

The only effective solution to start backup again is to delete the backup sparsedisk and start again.

Now this is not a great solution, because if you have backups it is to be able to return to them. Deleting the sparsedisk litterally deletes your backup capabilities and resets them to zero.

Apparently the problem is due to sparsedisk technicallity. Now this would mean that apple is not capable of writing a decent, reliable, file i/o system for their own in-house backup solution. This would be real deplorable.

Anyway, I have successfully mounted the sparsedisk and run disk utility repair on it. I did not fix the problem but it yielded the following message "Invalid sibling link" before it stopped.

Can anyone provide some help that does not involve deleting the backup disk.
 
Ok. I have been using time machine for around 7 months now. I have had issues as you are stating. For now, I have only experienced what causes these problems, not so much on how to fix them.

I have set Time Machine to backup to an external drive along with a network folder, the same idea as time capsule.

"Read only"
When I receive this error stating that time machine can not mount or back up because the contents are read only.... usually a reboot of the Time Capsule box or my network server and my machine generally fixes this issue.
If this did not work, I made a duplicate of my 80gb backup, deleted the read only one and then finally renamed the duplicate to the original name. That has also worked for me. More so on the firewire drive and not the network folder.

The above error solutions may also help with time machine giving the error that the volume cannot be mounted.

*All of these errors have occurred (for me) only when the volume being used by Time Machine is unmounted/ejected incorrectly. I have been diligent with making sure that my Time Machine ejects the drives in use, before I close the lid or disconnect from my network.

To stay away from these errors I also created my own sparse image using disk utility and named it correctly, using time machines method = ComputerName_MAC-address.sparsebundle.

Disk Warrior states that it can fix Time Machine drives. That may be a worth while helper to the Time Machine woes. All you need to do is ask yourself how much is your data worth to you...

If you try out Disk Warrior, this link may help. Linky
 
I had the same issue and was eventually able to fix it. I wrote up how I did it on OmniNerd: Fixing Time Capsule Read Only Error

Basically, it involves changing your computer and Time Capsule names, and then tricking Time Machine into using these new names for the backup.

I haven't had any issues with my backups since (i.e., for a few months).
 
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