Tag Archives: fsroot

Why Backups Matter (even when they don’t matter)

Apple continues its multi-year assault on my beloved “late 2011” 17 inch MacBook Pro. First by shipping it with a famously defective logic board, which I learned to repair by periodically baking and now by stymying my efforts to to restore backups to it.

When the 17-incher’s hard disk started to suffer from an “invalid fsroot tree” as reported by Disk Utility, I migrated my account over to a new 15 inch MacBook Pro and started using it as my primary computer. But the 17 kept chugging along and I continued to use it mainly for designing and slicing 3D prints for my awesome Prusa MK3S.

It wouldn’t support any OS after High Sierra and occasionally I was unable to open documents but the laptop performed well enough for its current purpose.

All the work I was creating on the 17″ Mac was either one-off stuff or stored in the cloud. So I saw no point in wasting storage and backing the laptop’s increasingly corrupt file system. When the time came, I would just reformat or replace its SSD and restore from the 15-incher’s backup. Easy peasy.

So the day finally came when ‘Ol Seventeen just kept crashing and I replaced it’s 1 TB SSD with a 2TB disk. I fired it up in Internet Restore mode (Command-Option-R), formatted the SSD, and installed High Sierra.

So just use Migration Assistant to restore my account from a Time Capsule backup, right? Nope, that didn’t show any valid backups to restore from. No problem, I could use Migration Assistant to push the account from the 15-inch to the 17-inch, correct? Um no, Apple wouldn’t have any of that either.

Backups from the 15″, which is running Catalina, could not be migrated to the older High Sierra OS. So instead of restoring my account the easy way using Migration Assistant, I will need to manually copy my stuff over from the 15″, reinstall applications, re-set preferences, re-enter passwords and all that kind of fun stuff. Uck.

So don’t assume that the migration tool that makes it so easy to move from an old to a new Mac works the other way around. In retrospect, I can understand why this isn’t just a diabolical plot to get me to buy another new Mac. There’s no practical way for an OS to know what incompatible applications, features or documents could be added in future operating systems, so no way to determine what stuff is compatible and what isn’t. Lesson learned.