KPROPD(8)

NAME
kpropd - Kerberos V5 slave KDC update server

SYNOPSIS
kpropd [ -r realm ] [ -f slave_dumpfile ] [ -F principal_database ] [ -p kdb5_util_prog ] [ -d ] [ -S ] [ -P port ]

DESCRIPTION
The kpropd command runs on the slave KDC server. It listens for update requests made by the kprop(8) program, and periodically requests incremental updates from the master KDC.

When the slave receives a kprop request from the master, kpropd accepts the dumped KDC database and places it in a file, and then runs kdb5_util(8) to load the dumped database into the active database which is used by krb5kdc(8). Thus, the master Kerberos server can use kprop(8) to propagate its database to the slave slavers. Upon a successful download of the KDC database file, the slave Kerberos server will have an up-to-date KDC database.

Normally, kpropd is invoked out of inetd(8). This is done by adding a line to the inetd.conf file which looks like this:

kprop    stream    tcp    nowait    root    /usr/local/sbin/kpropd    kpropd

However, kpropd can also run as a standalone daemon, if the -S option is turned on. This is done for debugging purposes, or if for some reason the system administrator just doesn't want to run it out of inetd(8).

When the slave periodically requests incremental updates, kpropd updates its principal.ulog file with any updates from the master. kproplog(8) can be used to view a summary of the update entry log on the slave KDC. Incremental propagation is not enabled by default; it can be enabled using the iprop_enable and iprop_slave_poll settings in kdc.conf(5). The principal "kiprop/slavehostname@REALM" (where "slavehostname" is the name of the slave KDC host, and "REALM" is the name of the Kerberos realm) must be present in the slave's keytab file.

OPTIONS

-r realm
    specifies the realm of the master server; by default the realm returned by krb5_default_local_realm(3) is used.

-f file
    specifies the filename where the dumped principal database file is to be stored; by default the dumped database file is KPROPD_DEFAULT_FILE (normally /usr/local/var/krb5kdc/from_master).

-p  allows the user to specify the pathname to the kdb5_util(8) program; by default the pathname used is KPROPD_DEFAULT_KDB5_UTIL (normally /usr/local/sbin/kdb5_util).

-S  turn on standalone mode. Normally, kpropd is invoked out of inetd(8) so it expects a network connection to be passed to it from inetd (8). If the -S option is specified, kpropd will put itself into the background, and wait for connections to the KPROP_SERVICE port (normally krb5_prop).

-d  turn on debug mode. In this mode, if the -S option is selected, kpropd will not detach itself from the current job and run in the background. Instead, it will run in the foreground and print out debugging messages during the database propagation.

-P  allow for an alternate port number for kpropd to listen on. This is only useful if the program is run in standalone mode.

-a  allows the user to specify the path to the kpropd.acl file; by default the path used is KPROPD_ACL_FILE (normally /usr/local/var/krb5kdc/kpropd.acl).

FILES

kpropd.acl
    Access file for kpropd; the default location is KPROPD_ACL_FILE (normally /usr/local/var/krb5kdc/kpropd.acl). Each entry is a line containing the principal of a host from which the local machine will allow Kerberos database propagation via kprop.

SEE ALSO
kprop(8), kdb5_util(8), krb5kdc(8), inetd(8)