NAME

       kafs-dns - AFS filesystem address resolution helper

SYNOPSIS

       /usr/libexec/kafs-dns [OPTION]... <key_serial>
       /usr/libexec/kafs-dns -D [OPTION]... <desc> <calloutinfo>
       /usr/libexec/kafs-dns -V

       Where options are:

              [-v] [-c <conffile>]* [-N <restriction>] [-o <dumpfile>]

DESCRIPTION

       This  program  is  invoked  by  the  request-key(8)  kernel  upcall handling program to handle an address
       resolution request on behalf of the in-kernel AFS filesystem driver to find the Volume  Location  servers
       for a cell.  It is capable of using static configuration, NSS and DNS SRV and AFSDB record lookups.

       Note  that this program is not meant to be called directly, though it does have a debugging mode that can
       be used.

       The first form of the command, without the -D flag cannot be called directly as  it  requires  an  under-
       construction kernel key as its parameter.

       The  debugging  form,  in  which  -D  is  given,  doesn't require a key, but must be given a proposed key
       description and a callout information string.  Information about what  it  is  doing  is  dumped  to  the
       output.   The  result blob may be binary and so is not dumped to stdout, but can be dumped to a file with
       -o <dumpfile>.

       The available options are:

ARGUMENTS

       -D     Execute in debug mode.

       -v     Increase the verbosity of the output.  This may be specified multiple times.

       -c <conffile>
              Specify a configuration file to read instead  of  the  system  default.   This  may  be  specified
              multiple times and the configuration files are read and applied in order.

       -N <restriction>
              Apply  a  restriction  to  the  lookup  performed for the listed cells (if any are).  Restrictions
              include:

              -N vl-srv
                     Don't use SRV records to find Volume Location servers.

              -N vl-afsdb
                     Don't use AFSDB records to find Volume Location servers.

              -N vl-all
                     Don't use SRV or AFSDB records to find Volume Location servers.

              -N vl-host
                     Don't look cell name up as hostname to find a Volume Location server.

              -N vl-dns
                     Don't do any lookups to find Volume Location servers.  Use only the static configuration.

       -o <dumpfile>
              Specify a file in which to dump the proposed payload with which to instantiate a resolver key.

       -V     Display version information and exit.

       The key description, <desc>, should be the name of a cell prefixed by "afsdb:".

       The callout information string, <calloutinfo>, is a comma separated list of none or more of the following
       items:

       ipv4   Get IPv4 addresses only.

       ipv6   Get IPv6 addresses only.

       srv=<ver>
              Allow the extra information that can be gleaned from SRV records to be rendered as  output  format
              <ver>, where <ver> is a number.

EXIT STATUS

       0      On success.

       1      If an error occurs during processing.

       2      If a command line error occurs.

       3      If bad configuration is detected.

EXAMPLE

       The program can be called with something like:

              /usr/libexec/kafs-dns -D afsdb:example.com srv=1

       The program can also be invoked indirectly with something like:

              keyctl request2 dns_resolver afsdb:example.com srv=1 @s

       which will return the serial number of a key that can then be displayed.

SEE ALSO

       kafs(7), kafs-client.conf(5), keyctl(1), request-key(8)

Linux                                              9 Jun 2020                                        KAFS-DNS(8)