NAME

       kafs - In-kernel AFS filesystem

DESCRIPTION

       "kafs" is a network filesystem driver in the Linux kernel that is able to access AFS cells
       and the servers contained therein to locate the logical volumes that comprise the cell and
       the files contained in each volume.

       It supports transport over IPv4 UDP and IPv6 UDP and security based on Kerberos.  The
       authentication token is used to define the user for the purpose of providing access
       control as well as providing communications security.

       The filesystem is of type "afs" and the mount command can be used to mount afs volumes
       manually using the "-t" flag on mount(8).

SETTING UP

       The "kafs-client" package should be installed to so that systemd is configured to include
       a mount of AFS dynamic root on /afs.  Note that mounting /afs is not enabled by default,
       so if it is needed, then "systemd" should be told to enable it.  This can be done with the
       following step:

             systemctl enable afs.mount

       This will mount a special directory on "/afs" which will be populated by an automount
       directory for each cell listed in the configuration.  Doing a pathwalk into one of these
       directories will result in the "afs.cell" volume from the cell being mounted onto that
       directory.

       Local configuration should be placed in a file in the /etc/kafs/client.d/ directory.  This
       will be included from /etc/client.conf file.

       Typically in the local configuration, the local cell name would be specified and backup
       details of its Volume Location server addresses would be given.

       Also any overrides for the @sys filename substitution would be specified.  See
       kafs-client.conf(5).

OPERATION

       Once the kafs-client is set up (and if there's no local cell, this is practically zero-
       conf, provided the cells to be accessed are properly set up with AFSDB or SRV records in
       the DNS), the /afs directory can be accessed:

             ls /afs/<cell>/location/within/cell

       For example:

             ls /afs/rivendell.example.com/doc

       The user isn't limited to cells listed in /afs, but any cell can be tried by just
       substituting the name of the cell into the above formula.  It does require the target to
       have DNS-based configuration provided.

       Note that each logical volume gets a discrete superblock and links between volumes turn
       into kernel mountpoints that, if stepped on, cause the appropriate volume to be mounted
       over them.

SECURITY

       kafs supports Kerberos-based authentication and communication encryption through the use
       of Kerberos.  "kinit" program can be use to authenticate with a Kerberos server:

             kinit myname@RIVENDELL.EXAMPLE.COM

       and then the "aklog-kafs" program to get a ticket for the kernel filesystem to use:

             aklog-kafs rivendell.example.com

       This will be placed on the caller's session keyring and can be viewed there with:

             keyctl show

       Note that the default realm is assumed to be the same as the cell name, but in all upper
       case.

SEE ALSO

       aklog-kafs(1), kafs-client.conf(5), keyctl(1), kinit(1), rxrpc(7), session-keyring(7),
       systemctl(1)

COPY RIGHT

       Copyright (C) 2019 Red Hat, Inc. All Rights Reserved.

       Written by David Howells (dhowells@redhat.com)

       This program is free software; you can redistribute it and/or modify it under the terms of
       the GNU General Public License as published by the Free Software Foundation; either
       version 2 of the License, or (at your option) any later version.