KAS(8) AFS Command Reference KAS(8)
kas - Introduction to the kas command suite
The commands in the kas command suite are the administrative interface to the Authentication Server, an obsolete AFS server process that
maintains the Authentication Database and provides the authentication tickets that client applications must present to AFS servers in order
to obtain access to AFS data and other services. It is used only for cells still running the Authentication Server until they can migrate
to a Kerberos version 5 KDC.
There are several categories of commands in the kas command suite:
o Commands to create, modify, examine and delete entries in the Authentication Database, including passwords: kas create, kas delete, kas
examine, kas list, kas setfields, kas setkey, kas setpassword, and kas unlock.
o Commands to create, delete, and examine tokens and server tickets: kas forgetticket, kas listtickets, kas noauthentication, and kas
o A command to enter interactive mode: kas interactive.
o A command to trace Authentication Server operations: kas statistics.
o Commands to obtain help: kas apropos and kas help.
Because of the sensitivity of information in the Authentication Database, the Authentication Server authenticates issuers of kas commands
directly, rather than accepting the standard token generated by the Ticket Granting Service. Any kas command that requires administrative
privilege prompts the issuer for a password. The resulting ticket is valid for six hours unless the maximum ticket lifetime for the issuer
or the Authentication Server's Ticket Granting Service is shorter.
To avoid having to provide a password repeatedly when issuing a sequence of kas commands, enter interactive mode by issuing the kas
interactive command, typing kas without any operation code, or typing kas followed by a user and cell name, separated by an at-sign ("@";
an example is "kas firstname.lastname@example.org"). After prompting once for a password, the Authentication Server accepts the resulting token for
every command issued during the interactive session. See kas_interactive(8) for a discussion of when to use each method for entering
interactive mode and of the effects of entering a session.
The Authentication Server maintains two databases on the local disk of the machine where it runs:
o The Authentication Database (/var/lib/openafs/db/kaserver.DB0) stores the information used to provide AFS authentication services to
users and servers, including the password scrambled as an encryption key. The reference page for the kas examine command describes the
information in a database entry.
o An auxiliary file (/var/lib/openafs/local/kaauxdb by default) that tracks how often the user has provided an incorrect password to the
local Authentication Server. The reference page for the kas setfields command describes how the Authentication Server uses this file to
enforce the limit on consecutive authentication failures. To designate an alternate directory for the file, use the kaserver command's
The kas command suite is provided only for administration of the obsolete Authentication Server for cells that have not yet migrated to a
Kerberos version 5 KDC. New deployments should not use the Authentication Server, and it and the kas command suite will be removed in a
future version of OpenAFS.
The following arguments and flags are available on many commands in the kas suite. (Some of them are unavailable on commands entered in
interactive mode, because the information they specify is established when entering interactive mode and cannot be changed except by
leaving interactive mode.) The reference page for each command also lists them, but they are described here in greater detail.
-admin_username <user name>
Specifies the user identity under which to authenticate with the Authentication Server for execution of the command. If this argument
is omitted, the kas command interpreter requests authentication for the identity under which the issuer is logged onto the local
machine. Do not combine this argument with the -noauth flag.
-cell <cell name>
Names the cell in which to run the command. It is acceptable to abbreviate the cell name to the shortest form that distinguishes it
from the other entries in the /etc/openafs/CellServDB file on the local machine. If the -cell argument is omitted, the command
interpreter determines the name of the local cell by reading the following in order:
o The value of the AFSCELL environment variable.
o The local /etc/openafs/ThisCell file.
The -cell argument is not available on commands issued in interactive mode. The cell defined when the kas command interpreter enters
interactive mode applies to all commands issued during the interactive session.
Prints a command's online help message on the standard output stream. Do not combine this flag with any of the command's other options;
when it is provided, the command interpreter ignores all other options, and only prints the help message.
Establishes an unauthenticated connection to the Authentication Server, in which the Authentication Server treats the issuer as the
unprivileged user "anonymous". It is useful only when authorization checking is disabled on the server machine (during the installation
of a server machine or when the bos setauth command has been used during other unusual circumstances). In normal circumstances, the
Authentication Server allows only privileged users to issue most kas commands, and refuses to perform such an action even if the
-noauth flag is provided. Do not combine this flag with the -admin_username and -password_for_admin arguments.
Specifies the password of the command's issuer. It is best to omit this argument, which echoes the password visibly in the command
shell, instead enter the password at the prompt. Do not combine this argument with the -noauth flag.
-servers <machine name>+
Establishes a connection with the Authentication Server running on each specified database server machine, instead of on each machine
listed in the local /etc/openafs/CellServDB file. In either case, the kas command interpreter then chooses one of the machines at
random to contact for execution of each subsequent command. The issuer can abbreviate the machine name to the shortest form that allows
the local name service to identify it uniquely.
To issue most kas commands, the issuer must have the "ADMIN" flag set in his or her Authentication Database entry (use the kas setfields
command to turn the flag on).
CellServDB(5), kaserver.DB0(5), kaserverauxdb(5), kas_apropos(8), kas_create(8), kas_delete(8), kas_examine(8), kas_forgetticket(8),
kas_help(8), kas_interactive(8), kas_list(8), kas_listtickets(8), kas_noauthentication(8), kas_quit(8), kas_setfields(8),
kas_setpassword(8), kas_statistics(8), kas_stringtokey(8), kas_unlock(8), kaserver(8)
IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.
This documentation is covered by the IBM Public License Version 1.0. It was converted from HTML to POD by software written by Chas
Williams and Russ Allbery, based on work by Alf Wachsmann and Elizabeth Cassell.
OpenAFS 2012-03-26 KAS(8)