dd clone procedure questions

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Evan

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Jan 6, 2016
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Yes CCC does everything including recover partitions.
Also what I use, costs a few $ now but depending on OS version maybe you can use an old copy pre $$.

Just buy it, very useful to have to migrate systems and create bare metal restores.
 
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Evan

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Jan 6, 2016
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It's actually based on rsync wth all the extras for the special stuff.
 

Evan

Well-Known Member
Jan 6, 2016
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dd should work I assume, other option maybe a copy/rsync and a 'repair' to make everything good and bootable again.
I have a spare Mac I can test something on if you need or get stuck.

Or why not just internet recovery on new disk to install base OS and mount the other disk and use migration assistant to migrate everything even programs ??
 

BLinux

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Jul 7, 2016
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I'm not a Mac user, but having used dd a lot in Linux, here's what I can offer. The different size shouldn't be a problem since the source is smaller than the destination. You'll end up with a partition table that doesn't know about the extra space, but you can change that later with gparted or other partition table editor. I don't know about the filesystem, but in Linux, ext4 or xfs can be expanded into resized partitions that have been expanded easily.

On the sector size issue, I don't think it will be a problem for the data copy, read 8x 512b sectors to write 1x 4k sector should be ok. The problem will be the boot sector, which at some point in the bootstrap must find something via LBA and that is likely to break. In Linux land it's not hard to rebuild the bootsect from a recovery CD or USB drive, idk about Mac but I would assume there is a procedure for it.
 
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rootgremlin

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Jun 9, 2016
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dd is the worst "tool" for this purpose you can use.
start your system with both drives attached, partition your ssd however you need and format one partition as hfs+. Copy (real filecopy) your files to the new drive/partition.
The booting on Macs is not a problem, since the Macintosh-EFI Bootloader is looking for specific *FILES* in /System/Library/kernels/kernel on HFS+ Volumes.
The most you have to do to finish the moving is to "Change the Mac Startup Drive on Boot" on the first reboot. (Holding Option-Key on Startup-Chime)
It is certainly not needed to transfer gigabytes of "NULL" data to the new SSD
 

rootgremlin

Member
Jun 9, 2016
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and please DO NOT use the finder to copy those Files.... you need a real copy, one that leaves Hard/Soft-Links intact, and also knows the difference between Files, Character-devicefiles and virtual Filesystems. (at worst commandline cp will do just fine)