My system was starting to get flakey, weird errors, lockups. Then Time Machine was failing to backup. At first I thought that the Time Machine drive was flakey, but after swapping it out, it still wouldn't work. After going through the Recovery dance (Disk First Aid, Repair Permissions, Directory rebuild with Disk Warrior) I concluded that really it was the system drive that had problems.
I bought a new drive, slapped it into an external carrier, and proceeded to restore my last good Time Machine to it. That went fine, I swapped it out, put it into the machine (laptop) but then I discovered it had no Recovery partition on the new drive.
Lion Recovery Assistant, available from Apple, probably works to install a Recovery partition to another drive, but it's boot drive has to have a Recovery partition on it.
By then, it was getting late. Did I really want to pull the drive from the laptop, hook it to another machine, add a new Recovery partition, then put it all back? No. I opted for the simpler approach that I should have used from the beginning - I could sleep while that has going on!
Really, the simplest way to setup a new disk to replace your old one seems to be:
- get a fresh OSX Lion installer (option+Purchases on App Store is one way) and install it;
- boot from your new Recovery partition (cmd+R), and Restore from Time Machine backup;
- reboot and apply Software Update.
This was aided by my having a bootable system that could talk to App Store and reinstall it. So maybe the extra step wasn't a total waste. Felt that way though.
One of those flash keys (prebuilt or diy) might also work.
Of course, this won't clone your Bootcamp partition if you're using one. I may not reinstall mine - i hardly used it before.