Can't generate a clone with disk-utility - strange errormessage

[harre63]

Hi,
I'm struggling to generate a clone from my iMac (2009, OSX 10.11.6) and my MacBook Pro (2010, macOS 10.12.2).
I've tried with two different external drives using disk-utility, but the result is always the same - it doesn't work.

External hard-drive was formatted as 'extended journal' and 'GUID', I did two partitions (one for iMac, the other for MacBook) and when I start the cloning by selecting the external drive as target and my Mac HD als source and start the process with 'recovery' I will get the following error messages:
'Validating target ...'
'Validating source ...'
'Source volume is read-write and cannot be unmounted, so it can't be block copied.'
'Action failed'

Any idea what I'm doing wrong?

Cheers, Harald

 

[MacInWin]

You are trying to do a block clone, but to do that the source drive has to be unmounted. Given that the source drive is your boot drive, it cannot be unmounted. In addition, a block clone requires that the source and destination have the same geometry, i.e., be the same size drive, preferably the same drive exactly. I don't think you can do a block clone from one drive to a partition on another drive. It's been a while since I last did a block clone, but I seem to recall it gets picky over drive geometry.

What you want is a FILE clone, where files are copied file for file, regardless of drive geometry. A better tool for cloning (it's easier) is either Carbon Copy Cloner or Super Duper!, both of which do clones very well. And with both of them you can clone the boot drive to a new drive or partition easily.

 

[harre63]

Jake, thanks for your fast response, very appreciated.

So in other words: Disk utility is not the right tool to generate a bootable clone of my Macs, right??

 

[harryb2448]

Use the software Jake suggests. They have trial software available, however the fully registered versions are very, very much faster.

I use SD and very Friday simply hook up my Thunderbolt external and Smart Update. This reads the internal, checks the clone, and makes any adjustments. Takes two to three minutes, the clone is bootable in case of troubles. If I have any files I wish to keep, I burn them to disc.

 

[chscag]

So in other words: Disk utility is not the right tool to generate a bootable clone of my Macs, right??

That's right. As Jake pointed out, use either Carbon Copy Cloner or SuperDuper. Both are pay apps but Carbon Copy Cloner has a 30 day free trial and is fully functional during the trial period. It's my cloning tool and backup tool of choice.

 

[harre63]

Thank you very much for your responses, I got the procedure described above from a macOS Sierra book and I will get back to the publisher that this procedure doesn't work.