I also recently (4 days ago) updated to Catalina 10.15.2.
I also had the same error as reported by the OP.
My solution went as per the answer above
but I had also used
macports to install
mongodb, and so it was installed with a view to using
/data/db as the default. Hence I ran into the problem described here.
MongoDB can't find data directory after upgrading to Mac OS 10.15 (Catalina)
That is, my
/data/db directory had been moved to
/Users/Shared/Relocated\ Items/Security/data/db. So
mongod still wouldn't start.
So I migrated my MacPorts installation to the Catalina version, by (mostly) following the instructions here:
Migrating MacPorts after a major operating system upgrade or from one computer to another
At the moment I am running
port upgrade outdated
The theory is that
mongod will be reinstalled in such a way as to work properly on Catalina. That way I avoid the misery of trying to work out how to write a valid
YAML file. I hate