I think this is a Catalina issue as I don't recall noticing it in Mojave.
I just installed the recently released supplemental update for Catalina and have noticed that all the log files in /Library/Logs have been removed after the upgrade. I took a snapshot on a VM and ran the upgrade a few more times just to confirm this is happening - it is.
Before the upgrade I have a folder /Library/Logs/MyComputerName. In this folder is where I put custom logs, including the log file for our update script. That entire folder is gone, and most of the log files under other folders in /Library/Logs are gone as well (though some empty folders still exist).
I read that Catalina has moved system files to a read-only operating system. I'm wondering if that could be part of this problem.
Does anyone know if this is the expected behavior? Is there a better/recommended place to store log files that will survive macOS updates?
Solved! Go to Solution.
I know this is a fairly old post, but just adding that I came across this exact same issue when upgrading from High Sierra to Mojave. Honestly did my head in for a while, as I would also lose my all my upgrade logs, so couldnt track what was happening.
Although very late to the plate, now planning the Catalina upgrade across the fleet, so good to know up front that this still occurs.