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       klog, klog.krb - Authenticates with the Authentication Server


       klog [-x] [-principal <user name>]
           [-password <users password>] [-cell <cell name>]
           [-servers <explicit list of servers>+]
           [-pipe] [-silent]
           [-lifetime <ticket lifetime in hh[:mm[:ss]]>]
           [-setpag] [-tmp] [-help]

       klog [-x] [-pr <user name>] [-pa <users password>]
           [-c <cell name>]  [-s <explicit list of servers>+]
           [-pi] [-si] [-l <ticket lifetime in hh[:mm[:ss]]>]
           [-se] [-t] [-h]

       klog.krb [-x] [-principal <user name>]
           [-password <users password>] [-cell <cell name>]
           [-servers <explicit list of servers>+]
           [-pipe] [-silent]
           [-lifetime <ticket lifetime in hh[:mm[:ss]]>]
           [-setpag] [-tmp] [-help]


       The klog command obtains an AFS token from the Authentication Server.
       The Cache Manager on the local machine stores the token in a credential
       structure in kernel memory and uses it when obtaining authenticated
       access to the AFS filespace. This command does not affect the issuer’s
       identity (UNIX UID) in the local file system.

       By default, the command interpreter obtains a token for the AFS user
       name that matches the issuer’s identity in the local file system. To
       specify an alternate user, include the -principal argument.  The user
       named by the -principal argument does not have to appear in the local
       password file (the /etc/passwd file or equivalent).

       By default, the command interpreter obtains a token for the local cell,
       as defined by the AFSCELL environment variable set in the command shell
       or by the /etc/openafs/ThisCell file on the local machine. To specify
       an alternate cell, include the -cell argument. The command interpreter
       contacts an Authentication Server chosen at random from the cell’s
       entry in the local /etc/openafs/server/CellServDB file, unless the
       -servers argument is used to name one or more database server machines.

       A user can have tokens in multiple cells simultaneously, but only one
       token per cell per connection to the client machine. If the user’s
       credential structure already contains a token for the requested cell,
       the token resulting from this command replaces it.

       Sites that employ Kerberos authentication instead of the AFS
       Authentication Server should normally use the combination of kinit and
       aklog instead of klog.

       Sites using Kerberos v4 authentication (perhaps with the AFS
       Authentication Server) should use the Kerberos version of this command,
       klog.krb, on all client machines. It automatically places the issuer’s
       Kerberos tickets in the file named by the KRBTKFILE environment
       variable, which the pagsh.krb command defines automatically as
       /tmp/tktpX where X is the number of the user’s PAG.

       The lifetime of the token resulting from this command is the smallest
       of the following.

       ·   The lifetime specified by the issuer with the -lifetime argument.
           If the issuer does not include this argument, the value defaults to
           720 hours (30 days).

       ·   The maximum ticket lifetime recorded for the afs entry in the
           Authentication Database. The default is 100 hours.

       ·   The maximum ticket lifetime recorded in the specified user’s
           Authentication Database entry. The default is 25 hours for user
           entries created by an Authentication Server running AFS 3.1 or

       ·   The maximum ticket lifetime recorded in the krbtgt.CELLNAME entry
           in the Authentication Database; this entry corresponds to the
           ticket-granting ticket used internally in generating the token. The
           default is 720 hours (30 days).

       The output from the kas examine command displays an Authentication
       Database entry’s maximum ticket lifetime as "Max ticket lifetime".
       Administrators can display any entry, and users can display their own

       If none of the defaults have been changed, the token lifetime is 25
       hours for user accounts created by an Authentication Server running AFS
       3.1 or higher. The maximum lifetime for any token is 720 hours (30
       days), and the minimum is 5 minutes.

       Between the minimum and maximum values, the Authentication Server uses
       a defined set of values, according to the following rules. Requested
       lifetimes between 5 minutes and 10 hours 40 minutes are granted at 5
       minute intervals, rounding up. For example, if the issuer requests a
       lifetime of 12 minutes, the token’s actual lifetime is 15 minutes.

       For token lifetimes greater than 10 hours 40 minutes, consult the
       following table, which presents all the possible times in units of
       hours:minutes:seconds.  The number in parentheses is an approximation
       of the corresponding time in days and hours (as indicated by the "d"
       and "h" letters). For example, "282:22:17" means 282 hours, 22 minutes,
       and 17 seconds, which translates to approximately 11 days and 18 hours
       ("11d 18h"). The Authentication Server rounds up a requested lifetime
       to the next highest possible lifetime.

          11:24:15 (0d 11h)    46:26:01 (1d 22h)  189:03:38 (7d 21h)
          12:11:34 (0d 12h)    49:38:40 (2d 01h)  202:08:00 (8d 10h)
          13:02:09 (0d 13h)    53:04:37 (2d 05h)  216:06:35 (9d 00h)
          13:56:14 (0d 13h)    56:44:49 (2d 08h)  231:03:09 (9d 15h)
          14:54:03 (0d 14h)    60:40:15 (2d 12h)  247:01:43 (10d 07h)
          15:55:52 (0d 15h)    64:51:57 (2d 16h)  264:06:34 (11d 00h)
          17:01:58 (0d 17h)    69:21:04 (2d 21h)  282:22:17 (11d 18h)
          18:12:38 (0d 18h)    74:08:46 (3d 02h)  301:53:45 (12d 13h)
          19:28:11 (0d 19h)    79:16:23 (3d 07h)  322:46:13 (13d 10h)
          20:48:57 (0d 20h)    84:45:16 (3d 12h)  345:05:18 (14d 09h)
          22:15:19 (0d 22h)    90:36:53 (3d 18h)  368:56:58 (15d 08h)
          23:47:38 (0d 23h)    96:52:49 (4d 00h)  394:27:37 (16d 10h)
          25:26:21 (1d 01h)   103:34:45 (4d 07h)  421:44:07 (17d 13h)
          27:11:54 (1d 03h)   110:44:28 (4d 14h)  450:53:46 (18d 18h)
          29:04:44 (1d 05h)   118:23:54 (4d 22h)  482:04:24 (20d 02h)
          31:05:22 (1d 07h)   126:35:05 (5d 06h)  515:24:22 (21d 11h)
          33:14:21 (1d 09h)   135:20:15 (5d 15h)  551:02:38 (22d 23h)
          35:32:15 (1d 11h)   144:41:44 (6d 00h)  589:08:45 (24d 13h)
          37:59:41 (1d 13h)   154:42:01 (6d 10h)  629:52:56 (26d 05h)
          40:37:19 (1d 16h)   165:23:50 (6d 21h)  673:26:07 (28d 01h)
          43:25:50 (1d 19h)   176:50:01 (7d 08h)


       By default, this command does not create a new process authentication
       group (PAG); see the description of the pagsh command to learn about
       PAGs. If a cell does not use an AFS-modified login utility, users must
       include -setpag option to this command, or issue the pagsh command
       before this one, to have their tokens stored in a credential structure
       that is identified by PAG rather than by local UID.

       When a credential structure is identified by local UID, the potential
       security exposure is that the local superuser "root" can use the UNIX
       su command to assume any other identity and automatically inherit the
       tokens associated with that UID. Identifying the credential structure
       by PAG eliminates this exposure.

       If the -password argument is used, the specified password cannot begin
       with a hyphen, because it is interpreted as another option name.  Use
       of the -password argument is not recommended in any case.

       By default, it is possible to issue this command on a properly
       configured NFS client machine that is accessing AFS via the NFS/AFS
       Translator, assuming that the NFS client machine is a supported system
       type. However, if the translator machine’s administrator has enabled
       UID checking by including the -uidcheck on argument to the fs exportafs
       command, the command fails with an error message similar to the

          Warning: Remote pioctl to <translator_machine> has failed (err=8). . .
          Unable to authenticate to AFS because a pioctl failed.

       Enabling UID checking means that the credential structure in which
       tokens are stored on the translator machine must be identified by a UID
       that matches the local UID of the process that is placing the tokens in
       the credential structure. After the klog command interpreter obtains
       the token on the NFS client, it passes it to the remote executor daemon
       on the translator machine, which makes the system call that stores the
       token in a credential structure on the translator machine. The remote
       executor generally runs as the local superuser "root", so in most cases
       its local UID (normally zero) does not match the local UID of the user
       who issued the klog command on the NFS client machine.

       Issuing the klog command on an NFS client machine creates a security
       exposure: the command interpreter passes the token across the network
       to the remote executor daemon in clear text mode.


       -x  Appears only for backwards compatibility. Its former function is
           now the default behavior of this command.

       -principal <user name>
           Specifies the user name to authenticate. If this argument is
           omitted, the Authentication Server attempts to authenticate the
           user logged into the local system.

       -password <users password>
           Specifies the issuer’s password (or that of the alternate user
           identified by the -principal argument). Omit this argument to have
           the command interpreter prompt for the password, in which case it
           does not echo visibly in the command shell.

       -cell <cell name>
           Specifies the cell for which to obtain a token. The command is
           directed to that cell’s Authentication Servers. During a single
           login session on a given machine, a user can be authenticated in
           multiple cells simultaneously, but can have only one token at a
           time for each of them (that is, can only authenticate under one
           identity per cell per session on a machine). It is acceptable to
           abbreviate the cell name to the shortest form that distinguishes it
           from the other cells listed in the /etc/openafs/CellServDB file on
           the client machine on which the command is issued.

           If this argument is omitted, the command is executed in the local
           cell, as defined

           ·   First, by the value of the environment variable AFSCELL.

           ·   Second, in the /etc/openafs/ThisCell file on the client machine
               on which the command is issued.

       -servers <explicit list of servers>+
           Establishes a connection with the Authentication Server running on
           each specified database server machine. The command interpreter
           then chooses one of these at random to execute the command. It is
           best to provide fully-qualified hostnames, but abbreviated forms
           are possibly acceptable depending on the state of the cell’s name
           server at the time the command is issued. This option is useful for
           testing specific servers if problems are encountered.

           If this argument is omitted, the command interpreter establishes a
           connection with each machine listed for the indicated cell in the
           local copy of the /etc/openafs/CellServDB file, and then chooses
           one of them at random for command execution.

           Suppresses all output to the standard output stream, including
           prompts and error messages. The klog command interpreter expects to
           receive the password from the standard input stream. Do not use
           this argument; it is designed for use by application programs
           rather than human users.

           Suppresses some of the trace messages that the klog command
           produces on the standard output stream by default. It still reports
           on major problems encountered.

       -lifetime <ticket lifetime
           Requests a specific lifetime for the token. Provide a number of
           hours and optionally minutes and seconds in the format
           hh[:mm[:ss]].  The value is used in calculating the token lifetime
           as described in DESCRIPTION.

           Creates a process authentication group (PAG) prior to requesting
           authentication. The token is associated with the newly created PAG.

           Creates a Kerberos-style ticket file in the /tmp directory of the
           local machine. The file is called tkt.AFS_UID where AFS_UID is the
           AFS UID of the issuer.

           Prints the online help for this command. All other valid options
           are ignored.


       The following message indicates that the limit on consecutive
       authentication failures has been exceeded. An administrator can use the
       kas unlock command to unlock the account, or the issuer can wait until
       the lockout time for the account has passed. (The time is set with the
       -locktime argument to the kas setfields command and displayed in the
       output from the kas examine command).

          Unable to authenticate to AFS because ID is locked - see your system admin

       If the -tmp flag is included, the following message confirms that a
       Kerberos-style ticket file was created:

          Wrote ticket file to /tmp


       Most often, this command is issued without arguments. The appropriate
       password is for the person currently logged into the local system. The
       ticket’s lifetime is calculated as described in DESCRIPTION (if no
       defaults have been changed, it is 25 hours for a user whose
       Authentication Database entry was created in AFS 3.1 or later).

          % klog

       The following example authenticates the user as admin in the ABC
       Corporation’s test cell:

          % klog -principal admin -cell

       In the following, the issuer requests a ticket lifetime of 104 hours 30
       minutes (4 days 8 hours 30 minutes). Presuming that this lifetime is
       allowed by the maximum ticket lifetimes and other factors described in
       DESCRIPTION, the token’s lifetime is 110:44:28, which is the next
       largest possible value.

          % klog -lifetime 104:30




       fs_exportafs(1), kas_examine(8), kas_setfields(8), kas_unlock(8),
       kaserver(8), pagsh(1), tokens(1)


       IBM Corporation 2000. <> 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.