Mongod Service start exits with code 100
You may still have some problems with the permissions in your data directory. Especially if you have run mongod from the terminal to start with.
I find that the data files are created under root not the mongodb user when you run from the terminal. To fix ..
cd /var/lib/mongodbsudo chown -R mongodb:mongodb *
rm /var/lib/mongodb/mongod.locksystemctl restart mongodsystemctl status mongodTry this!
Remove the mongod.lock file under 'dbath', and it should start without issues.