Creating the kerberos database

We use a utility for creating that database: kdb5_util. If you cannot find that binary, then ask rpm where it is:
rpm -qal |grep kdb_util
Now we create the db:
/usr/lib/mit/sbin/kdb5_util create -r REDFLO.DE -s
Loading random data
Initializing database '/var/lib/kerberos/krb5kdc/principal' for realm 'REDFLO.DE',
master key name 'K/M@REDFLO.DE'
You will be prompted for the database Master Password.
It is important that you NOT FORGET this password.
Enter KDC database master key: 
Re-enter KDC database master key to verify: 

The -s creates a "stash file" which is needed to be able to start the kerberos servers at boot time. For more discussion see the kerberos installtion guide. You will be asked for the master database password. Choose a secure. As far as i know you won't need it any more, but i'm not sure (todo: check that!)