NAME

       ThisCell - Defines the local cell name

DESCRIPTION

       The ThisCell file defines the local cell name.  There are two versions of this file, one
       for a AFS client and one for an AFS server.

   Client ThisCell
       The client version of the ThisCell file defines the complete Internet domain-style name
       (for example, "example.com") of the cell to which the local client machine belongs. It
       must reside in the /etc/openafs directory on every AFS client machine. To change a client
       machine's cell membership, edit the file and reboot the machine.

       The file is in ASCII format and contains a character string on a single line. The OpenAFS
       Quick Start Guide instructs the administrator to create it during the installation of each
       client machine.

       The client machine's cell membership determines three defaults important to its
       functioning:

       •   The cell in which the machine's users authenticate by default.  The effect is two-
           fold:

           •   The AFS-modified login utilities and the klog command interpreter contact an
               Authentication Server in the cell named in the ThisCell file (unless -cell
               argument to the klog command specifies an alternate cell).

           •   The command interpreters combine the cell name with the password that the user
               provides, generating an encryption key from the combination. For authentication to
               succeed, both the cell name and password must match the ones used to generate the
               user's encryption key stored in the Authentication Database.

       •   The cell the Cache Manager considers its local, or home, cell. By default, the Cache
           Manager allows programs that reside in its home cell to run with setuid permission,
           but not programs from foreign cells. For more details, see the fs getcellstatus and fs
           setcell reference pages.

       •   Which AFS server processes the local AFS command interpreters contact by default as
           they execute commands issued on the machine.

       The client version of the ThisCell file is distinct from the server version, which resides
       in the /etc/openafs/server directory on each AFS server machine. If a server machine also
       runs as a client, it is acceptable for the server and client versions of the file on the
       same machine to name different cells. However, the behavior that results from this
       configuration can be more confusing than useful.

   Server ThisCell
       The server version of the ThisCell file defines the complete Internet domain-style name
       (for example, "example.com") of the cell to which the server machine belongs. It must
       reside in the /etc/openafs/server directory on every AFS server machine.

       The file is in ASCII format and contains a character string on a single line. The initial
       version of the file is created with the bos setcellname command during the installation of
       the cell's first file server machine, and the OpenAFS Quick Start Guide includes
       instructions for copying it over to additional server machine during their installation.

       The only reason to edit the file is as part of changing the cell's name, which is strongly
       discouraged because of the large number of configuration changes involved. In particular,
       changing the cell name requires rebuilding the entire Authentication Database, because the
       Authentication Server combines the cell name it finds in this file with each user and
       server password and converts the combination into an encryption key before recording it in
       the Database.

SEE ALSO

       bos_setcellname(8), fs_getcellstatus(1), fs_setcell(1)

COPYRIGHT

       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.