Вы открытый порт на Вашей группе безопасности 80 проверяют следующий URL
http://studyhat.blogspot.com/2010/08/using-amazon-web-services.html
The stash file created along with realm isn't useful while using OpenLDAP back-end as it doesn't contain DN. It looks like standalone stash file.
You have to create stash file with:
kdb5_ldap_util -D "cn=admin,dc=example,dc=com" stashsrvpw -f /var/kerberos/krb5kdc/example_stash.keyfile "cn=krbadmin,ou=Services,dc=example,dc=com"
Another thing that krb5.conf doesn't support inline comments.