Setting up a Kerberos 5 client is less involved than setting up a server. At a minimum, install the client packages and provide each client with a valid
krb5.conf configuration file. Kerberized versions of
rlogin also requires some configuration changes.
Be sure that time synchronization is in place between the Kerberos client and the KDC. Refer to Section 19.5, “Configuring a Kerberos 5 Server”
for more information. In addition, verify that DNS is working properly on the Kerberos client before configuring the Kerberos client programs.
krb5-workstation packages on all of the client machines. Supply a valid
/etc/krb5.conf file for each client (usually this can be the same
krb5.conf file used by the KDC).
Before a workstation in the realm can allow users to connect using kerberized
rlogin, that workstation must have the
xinetd package installed and have its own host principal in the Kerberos database. The
klogind server programs also need access to the keys for their service's principal.
kadmin, add a host principal for the workstation on the KDC. The instance in this case is the hostname of the workstation. Use the
-randkey option for the
addprinc command to create the principal and assign it a random key:
addprinc -randkey host/blah.example.com
Now that the principal has been created, keys can be extracted for the workstation by running
kadmin on the workstation itself, and using the
ktadd command within
ktadd -k /etc/krb5.keytab host/blah.example.com
To use other kerberized network services, they must first be started. Below is a list of some common kerberized services and instructions about enabling them:
rlogin — To use the kerberized versions of
Telnet — To use kerberized Telnet,
krb5-telnet must be enabled.
FTP — To provide FTP access, create and extract a key for the principal with a root of
ftp. Be certain to set the instance to the fully qualified hostname of the FTP server, then enable
IMAP — To use a kerberized IMAP server, the
cyrus-imap package uses Kerberos 5 if it also has the
cyrus-sasl-gssapi package installed. The
cyrus-sasl-gssapi package contains the Cyrus SASL plugins which support GSS-API authentication. Cyrus IMAP should function properly with Kerberos as long as the
cyrus user is able to find the proper key in
/etc/krb5.keytab, and the root for the principal is set to
imap (created with
dovecot package also contains an IMAP server alternative to
cyrus-imap, which is also included with Red Hat Enterprise Linux, but does not support GSS-API and Kerberos to date.
CVS — To use a kerberized CVS server,
gserver uses a principal with a root of
cvs and is otherwise identical to the CVS
For details about how to enable services, refer to the chapter titled Controlling Access to Services in the System Administrators Guide.