Configure the AD Domain on the KDC and Hadoop Cluster Hosts
Add the AD domain as a realm to the krb5.conf on the Hadoop cluster hosts. Optionally configure encryption types and UDP preferences.
- Open the krb5.conf file with a text editor and make the following changes: - To libdefaults, add the following properties. - Set the Hadoop realm as default: - [libdefaults] default_domain = $hadoop.realm 
- Set the encryption type: - [libdefaults] default_tkt_enctypes = $encryption_types default_tgs_enctypes = $encryption_types permitted_enctypes = $encryption_types - where the $encryption_types match the type supported by your environment. - For example: - default_tkt_enctypes = aes256-cts aes128-cts rc4-hmac arcfour-hmac-md5 des-cbc-md5 des-cbc-crc default_tgs_enctypes = aes256-cts aes128-cts rc4-hmac arcfour-hmac-md5 des-cbc-md5 des-cbc-crc permitted_enctypes = aes256-cts aes128-cts rc4-hmac arcfour-hmac-md5 des- cbc-md5 des-cbc-crc 
- If TCP is open on the KDC and AD Server: - [libdefaults] udp_preference_limit = 1 
 
- Add a realm for the AD domain: - [realms] $AD.DOMAIN = { kdc = $AD-host-FQDN admin_server = $AD-host-FQDN default_domain = $AD-host-FQDN }
- Save the krb5.conf changes to all Hadoop Cluster hosts. 
 
- Add the trust principal for the AD domain to the Hadoop MIT KDC: - kadmin kadmin:addprinc krbtgt/$hadoop.realm@$AD.domain - This command will prompt you for the trust password. Use the same password as the earlier step. ![[Note]](../common/images/admon/note.png) - Note - If the encryption type was defined, then use the following command to configure the AD principal: - kadmin:addprinc -e "$encryption_type"krbtgt/$hadoop. realm@$AD.domain - When defining encryption, be sure to also enter the encryption type (e.g., 'normal') 

