automatic kinit

To automatic renew kerberos ticket by using ktutil:

ktutil
ktutil:  addent -password -p foo@dummy.domain -k 1 -e rc4-hmac
Password for foo@dummy.domain:
ktutil:  addent -password -p foo@dummy.domain -k 1 -e aes256-cts
Password for foo@dumy.domain:
ktutil:  wkt foo.keytab
ktutil:  quit

Then under shell we can run kinit foo@dummy.domain -k -t /folder/to/key/foo.keytab