Accessing old Time Machine backups after complete new OS install

I have multiple Macs back up over wifi to a NAS box. It is works well for recovering individual files, but not for recovery from a crash. When my laptop crashes, I cannot access my NAS until I first use Internet Recovery Mode to do a clean install of the OS. But once I do that, I have not been able to access the the old Time Machine backups. Seems to treat them as backups from a different computer. Is there an easy way to get access to the old backup files?

Any help much appreciated.

This is referred to as “inheriting” a Time Machine backup.

It is possible.

It is not extremely difficult, but it will require some work on the command-line.

Glenn Fleishman has a decent write-up here:

You can find others by searching for ‘inherit time machine backup’.

I’ve done this a time or two, not enough to feel like an expert, but enough that if you have questions, I’ll be happy to try to answer them.

Thank you. I will dig into this and let you know if I have questions. I can already se that knowing the term “inherit” opens up a huge trove of information on my problem.

A huge trove of information my problem.

Thanks again.

Glad to help. I originally searched for “adopt time machine backup” but knew that wasn’t quite the right word. Fortunately the search engines knew what I meant. But you’re right, sometimes just knowing the right term is the difference between finding the right information and finding none.