Securing ZooKeeper with Kerberos
When NiFi communicates with ZooKeeper, all communications, by default, are non-secure, and anyone who logs into ZooKeeper is able to view and manipulate all of the NiFi state that is stored in ZooKeeper. To prevent this, one option is to use Kerberos to manage authentication.
In order to secure the communications with Kerberos, we need to ensure that both the client and the server support the same configuration. Instructions for configuring the NiFi ZooKeeper client and embedded ZooKeeper server to use Kerberos are provided below.
If Kerberos is not already setup in your environment, you can find information on installing and setting up a Kerberos Server at Red Hat Customer Portal: Configuring a Kerberos 5 Server. This guide assumes that Kerberos already has been installed in the environment in which NiFi is running.
Note, the following procedures for kerberizing an Embedded ZooKeeper server in your NiFi Node and kerberizing a ZooKeeper NiFi client will require that Kerberos client libraries be installed. This is accomplished in Fedora-based Linux distributions via:
yum install krb5-workstation
Once this is complete, the /etc/krb5.conf will need to be configured appropriately for your organization's Kerberos environment.