[mikebore]

I have a Lacie external portable USB/FW drive which has a "Utilities" OS partition on it. I use SD to clone this volume to the Lacie from an internal "Utilities" partition.

This works fine for months on end, with the Lacie able to boot either my MBP or my Mac Pro fine either USB or FW.

Then out of the blue it stops booting the Mac Pro by FW. Just stops at the grey apple. It will still boot the MP by USB, and it will still boot the MBP by FW or USB, just not the MP by FW.

I have troubleshot the clone at this point extensively, including Diskwarrior, permissions, caches, PRAM, SMC etc etc. Even an erase-then-SD doesn't solve it.

I discovered that if I force a Lacie firmware update (to the same version) at this point the problem is solved, enabling it to boot for another few months until the next time.

Thinking this indicated a problem with the HD I sent it to Lacie who could find nothing wrong.

More recently I have discovered an alternative to the firmware fix. If re-run the clone process (smart update not erase) using Chronosync or Carbon Copy Cloner, it will boot the MP by FW again.

So now I think there is something very subtle about SD compared to CCC and Chronosync causing this intermittent behaviour.

Any comment or suggestions? I like SD best and would like not to have to use the others when the problem happens.

Thanks!