This command starts the KADM5 administration server. The administration
server runs on the master Kerberos server, which stores the KDC
principal database and the KADM5 policy database.
Kadmind accepts remote requests to administer the information in these
databases. Remote requests are sent, for example, by
kadmin(8) and the
kpasswd(1) command, both of which are clients of
kadmind .
kadmind requires a number of configuration files to be set up in order
for it to work:
kdc.conf
The KDC configuration file contains configuration informatin for the KDC
and the KADM5 system.
Kadmind understands a number of variable settings in this file, some of whch are
mandatory and some of which are optional. See the CONFIGURATION VALUES
section below.
keytab
Kadmind requires a keytab containing correct entries for the
kadmin/admin and
kadmin/changepw principals for every realm that kadmind will answer requests for. The
keytab can be created with the
kadmin(8) client. The location of the keytab is determined by the
admin_keytab configuration variable (see CONFIGURATION VALUES).
ACL file
Kadmind 's ACL (access control list) tells it which principals are allowed to
perform KADM5 administration actions. The path of the ACL file is
specified via the acl_file configuration variable (see CONFIGURATION
VALUES). The syntax of the ACL file is specified in the ACL FILE SYNTAX
section below.
After the server begins running, it puts itself in the background and
disassociates itself from its controlling terminal.
OPTIONS
-rrealm
specifies the default realm that kadmind will serve; if it is not
specified, the default realm of the host is used.
kadmind will answer requests for any realm that exists in the local KDC database
and for which the appropriate principals are in its keytab.
-m
specifies that the master database password should be fetched from the
keyboard rather than from a file on disk. Note that the server gets the
password prior to putting itself in the background; in combination with
the -nofork option, you must place it in the background by hand.
-nofork
specifies that the server does not put itself in the background and does
not disassociate itself from the terminal. In normal operation, you
should always allow the server place itself in the background.
-portport-number
specifies the port on which the administration server listens for
connections. The default is is controlled by the
kadmind_port configuration variable (see below).
CONFIGURATION VALUES
In addition to the relations defined in kdc.conf(5) , kadmind
understands the following relations, all of which should
appear in the [realms] section:
acl_file
The path of kadmind's ACL file. Mandatory. No default.
dict_file
The path of kadmind's password dictionary. A principal with any
password policy will not be allowed to select any password in the
dictionary. Optional. No default.
admin_keytab
The name of the keytab containing entries for the principals
kadmin/admin and
kadmin/changepw in each realm that
kadmind will serve. The default is the value of the
KRB5_KTNAME environment variable, if defined. Mandatory.
kadmind_port
The
TCP port on which
kadmind will listen. The default is 749.
ACL FILE SYNTAX
The ACL file controls which principals can or cannot perform which
administrative functions. For operations that affect principals, the
ACL file also controls which principals can operate on which other
principals. This file can contain comment lines, null lines or lines
which contain ACL entries. Comment lines start with the sharp sign
(#) and continue until the end of the line. Lines containing ACL
entries have the format of
principal whitespace operation-mask [whitespaceoperation-target]
Ordering is important. The first matching entry is the one which will
control access for a particular principal on a particular principal.
principal
may specify a partially or fully qualified Kerberos version 5
principal name. Each component of the name may be wildcarded using
the asterisk (
* ) character.
operation-target
[Optional] may specify a partially or fully qualified Kerberos version 5
principal name. Each component of the name may be wildcarded using the
asterisk (
* ) character.
operation-mask
Specifies what operations may or may not be peformed by a principal
matching a particular entry. This is a string of one or more of the
following list of characters or their upper-case counterparts. If the
character is upper-case, then the operation is disallowed. If the
character is lower-case, then the operation is permitted.
a
[Dis]allows the addition of principals or policies in the database.
d
[Dis]allows the deletion of principals or policies in the database.
m
[Dis]allows the modification of principals or policies in the database.
c
[Dis]allows the changing of passwords for principals in the database.
i
[Dis]allows inquiries to the database.
l
[Dis]allows the listing of principals or policies in the database.
x
Short for
admcil .
*
Same as
x .
Some examples of valid entries here are:
user/instance@realm adm
A standard fully qualified name. The
operation-mask only applies to this principal and specifies that [s]he may add,
delete or modify principals and policies, but not change anybody
else's password.
user/instance@realm cim service/instance@realm
A standard fully qualified name and a standard fully qualified target. The
operation-mask only applies to this principal operating on this target and specifies that
[s]he may change the target's password, request information about the
target and modify it.
user/*@realm ac
A wildcarded name. The
operation-mask applies to all principals in realm "realm" whose first component is
"user" and specifies that [s]he may add principals and change
anybody's password.
user/*@realm i */instance@realm
A wildcarded name and target. The
operation-mask applies to all principals in realm "realm" whose first component is
"user" and specifies that [s]he may perform
inquiries on principals whose second component is "instance" and realm
is "realm".
FILES
principal.db
default name for Kerberos principal database
<dbname>.kadm5
KADM5 administrative database. (This would be "principal.kadm5", if you
use the default database name.) Contains policy information.
<dbname>.kadm5.lock
lock file for the KADM5 administrative database. This file works
backwards from most other lock files. I.e.,
kadmin will exit with an error if this file does
not exist.
kadm5.acl
file containing list of principals and their
kadmin administrative privileges. See above for a description.
kadm5.keytab
keytab file for
kadmin/admin principal.
kadm5.dict
file containing dictionary of strings explicitly disallowed as
passwords.
