Datanodes under Hadoop is traditionally secured by creating a Keytab file on the datanodes. With Ozone, we have moved away to using datanode certificates. That is, Kerberos on datanodes is not needed in case of a secure Ozone cluster.
However, we support the legacy Kerberos based Authentication to make it easy for the current set of users.The HDFS configuration keys are the following that is setup in hdfs-site.xml.
|dfs.datanode.kerberos.principal||The datanode service principal.
|dfs.datanode.keytab.file||The keytab file used by datanode daemon to login as its service principal.|
|hdds.datanode.http.auth.kerberos.principal||Datanode http server service principal.|
|hdds.datanode.http.auth.kerberos.keytab||The keytab file used by datanode http server to login as its service principal.|
Under Ozone, when a datanode boots up and discovers SCM’s address, the first thing that datanode does is to create a private key and send a certificate request to the SCM.
Once a certificate is issued, a datanode is secure and Ozone manager can issue block tokens. If there is no datanode certificates or the SCM’s root certificate is not present in the datanode, then datanode will register itself and download the SCM’s root certificate as well get the certificates for itself.Next >>