System Administration Guide: Security Services

ProcedureHow to Reconfigure a Master KDC to Use Incremental Propagation

The steps in this procedure can be used to reconfigure an existing master KDC to use incremental propagation. In this procedure, the following configuration parameters are used:

  1. Add entries to kdc.conf.

    You need to enable incremental propagation and select the number of updates the KDC master keeps in the log. See the kdc.conf(4) man page for more information.


    kdc1 # cat /etc/krb5/kdc.conf
    [kdcdefaults]
            kdc_ports = 88,750
    
    [realms]
            EXAMPLE.COM= {
                    profile = /etc/krb5/krb5.conf
                    database_name = /var/krb5/principal
                    admin_keytab = /etc/krb5/kadm5.keytab
                    acl_file = /etc/krb5/kadm5.acl
                    kadmind_port = 749
                    max_life = 8h 0m 0s
                    max_renewable_life = 7d 0h 0m 0s
                    sunw_dbprop_enable = true
                    sunw_dbprop_master_ulogsize = 1000
            }
  2. Create the kiprop principal.

    The kiprop principal is used to authenticate the master KDC server and to authorize updates from the master KDC.


    kdc1 # /usr/sbin/kadmin -p kws/admin
    Enter password: <Type kws/admin password>
    kadmin: addprinc -randkey kiprop/kdc1.example.com
    Principal "kiprop/kdc1.example.com@EXAMPLE.COM" created.
    kadmin: addprinc -randkey kiprop/kdc2.example.com
    Principal "kiprop/kdc2.example.com@EXAMPLE.COM" created.
    kadmin:
  3. Add the kiprop principal to the kadmind keytab file

    Adding the kiprop principal to the kadm5.keytab file allows the kadmind command to authenticate itself when it is started.


    kadmin: ktadd -k /etc/krb5/kadm5.keytab kiprop/kdc1.example.com
    Entry for principal kiprop/kdc1.example.com with kvno 3, encryption type AES-256 CTS mode
              with 96-bit SHA-1 HMAC added to keytab WRFILE:/etc/krb5/kadm5.keytab.
    Entry for principal kiprop/kdc1.example.com with kvno 3, encryption type AES-128 CTS mode
              with 96-bit SHA-1 HMAC added to keytab WRFILE:/etc/krb5/kadm5.keytab.
    Entry for principal kiprop/kdc1.example.com with kvno 3, encryption type Triple DES cbc
              mode with HMAC/sha1 added to keytab WRFILE:/etc/krb5/kadm5.keytab.
    Entry for principal kiprop/kdc1.example.com with kvno 3, encryption type ArcFour
              with HMAC/md5 added to keytab WRFILE:/etc/krb5/kadm5.keytab.
    Entry for principal kiprop/kdc1.example.com with kvno 3, encryption type DES cbc mode
              with RSA-MD5 added to keytab WRFILE:/etc/krb5/kadm5.keytab.
    kadmin: quit
    
  4. On the master KDC, add a kiprop entry to kadm5.acl

    This entry allows the master KDC to receive requests for incremental propagation from the kdc2 server.


    kdc1 # cat /etc/krb5/kadm5.acl
    */admin@EXAMPLE.COM *
    kiprop/kdc2.example.com@EXAMPLE.COM p
    
  5. Comment out the kprop line in the root crontab file.

    This step prevents the master KDC from propagating its copy of the KDC database.


    kdc1 # crontab -e
    #ident  "@(#)root       1.20    01/11/06 SMI"
    #
    # The root crontab should be used to perform accounting data collection.
    #
    # The rtc command is run to adjust the real time clock if and when
    # daylight savings time changes.
    #
    10 3 * * * /usr/sbin/logadm
    15 3 * * 0 /usr/lib/fs/nfs/nfsfind
    1 2 * * * [ -x /usr/sbin/rtc ] && /usr/sbin/rtc -c > /dev/null 2>&1
    30 3 * * * [ -x /usr/lib/gss/gsscred_clean ] && /usr/lib/gss/gsscred_clean
    #10 3 * * * /usr/lib/krb5kprop_script kdc2.example.sun.com #SUNWkr5ma
  6. Restart kadmind.


    kdc1 # svcadm restart network/security/kadmin
    
  7. Reconfigure all slave KDC servers that use incremental propagation.

    See How to Reconfigure a Slave KDC to Use Incremental Propagation for complete instructions.