Fix sudo yum hang problem with no output or error messages

Encounter a weird error this morning while trying to execute sudo yum update command. Yum just hangs there and no error messages whatsoever were displayed on screen. Have to issue kill -9 to terminate the yum process.

To fix the problem, first :

cd /var/lib/rpm

and then remove the __db.00* files. All of them.

and run this command

/usr/lib/rpm/rpmdb_recover

Run the sudo yum update command again and everything back to normal again!

Hope this helps.