DVT(1)                     OpenBSD Reference Manual                     DVT(1)

NAME
     dvt - launch an interactive window on a cluster of machines

SYNOPSIS
     dvt [-eiqv] [-f fanout] [-g rungroup1,...,rungroupN] [-l username]
         [-w node1,...,nodeN] [-x node1,...,nodeN]

DESCRIPTION
     The dvt utility launches a number of terminal windows, one for each
     machine the user specifies on the command line.  In addition, it launches
     a single control window.  The terminal windows are similar to terminal
     windows provided by xterm(1), xvt(1) or rxvt(1) in most regards, and may
     be used as a standard terminal window by themselves.  The control window
     however, allows global control of all the terminal windows.  The user can
     type in the command box of the control window, and the keystrokes will be
     sent to all the terminal windows at once.  In this way the user can
     perform interactive commands, such as editing a file, in parallel.  At
     any point, the user can switch his keyboard focus to a particular window,
     and issue commands to that window only, should it become neccesary.  The
     following options are available:

     -e   Unless the -e option is specified, stderr from remote commands will
          not be reported to the user.

     -i   The -i option will list information about the current cluster, and
          command groupings.  It will print out the current value of the
          fanout, and how many groups of machines there are within the
          cluster. It will also show you which command you are about to run,
          and your username if specified with the -l option.

     -q   The -q option does not issue any commands, but displays information
          about the cluster, and the fanout groupings.

     -v   Prints the version of ClusterIt to the stdout, and exits.

     -f   If the -f option is specified, followed by a number, it sets the
          fanout size of the cluster.  The fanout size is the number of nodes
          a command will run on in parallel at one time.  The fanout option,
          restricts the maximum number of windows that can be opened at one
          time.  This is used to prevent the user from accidentally launching
          hundreds of windows, and crashing their X-terminal, or server.  The
          fanout size defaults to 64.  This option overrides the FANOUT
          environment variable.

     -g   If the -g option is specified, followed by a comma separated list of
          group names, the command will only be run on that group of nodes.  A
          node may be a part of more than one group if desired, however
          running without the -g option will open windows to the same node as
          many times as it appears in the file specified by the CLUSTER
          environment variable.  This option is silently ignored if used with
          the -w option.

     -l   If the -l option is specified, followed by a username, the initial
          connection attempted will pass the username argument and attempt to
          login with that account to the remote system. Consideration must be
          taken for proper authentication, for this to work.

     -w   If the -w option is specified, followed by a comma delimited list of
          machine names, windows will be opened to each node in the list.
          Without this option, dvt open windows to all the nodes listed in the
          file pointed to by the CLUSTER environment variable.

     -x   The -x option can be used to exclude specific nodes from the
          cluster.  The format is the same as the -w option, a comma delimited
          list of machine names.  This option is silently ignored if used with
          the -w option.

ENVIRONMENT
     dvt utilizes the following environment variables.

     CLUSTER       Contains a filename, which is a newline separated list of
                   nodes in the cluster.

     RVT_CMD       Contains the name of a binary to be executed by dvt which
                   will open a terminal window and connection to a single
                   remote host.  The user may override this with another
                   program that performs the same function, however, the
                   program must supply as it's only output to stdout, it's X
                   Window-ID in decimal.  In addition, it must take as the
                   final argument, the name of a remtoe machine to connect to.
                   This program must also be capable of recieving X events
                   sent via the XSendEvent(3) facility.  If this environment
                   variable is not set, it defaults to rvt

     RVT_CMD_ARGS  Contains any additional arguments that you wish to pass to
                   the rvt command.  This can be used to set things like
                   colors, reverse video, etc in the terminal windows.

     FANOUT        When set, limits the maximum number of terminal windows to
                   open simultaneously.  This is designed to safeguard the
                   user from potentially opening hundreds of windows, and
                   overloading the X-terminal or server. Defaults to 64.  This
                   environment setting can be overridden by the -f option.

FILES
     The file pointed to by the CLUSTER environment variable has the following
     format:

           pollux
           castor
           GROUP:alpha
           rigel
           kent
           GROUP:sparc
           alshain
           altair
           LUMP:alphasparc
           alpha
           sparc

     This example would have pollux and castor a member of no groups, rigel
     and kent a member of group 'alpha', and alshain and altair a member of
     group `sparc'.  Note the format of the GROUP command, it is in all
     capital letters, followed by a colon, and the group name.  There can be
     no spaces following the GROUP command, or in the name of the group.

     There is also a LUMP command, which is identical in syntax to the GROUP
     command.  This command allows you to create a named group of groups.
     Each member of the lump is the name of a group.  The LUMP command is
     terminated by another LUMP or GROUP command, or the EOF marker.

     Any line beginning with a `#' symbol denotes a comment field, and the
     entire line will be ignored.  Note that a hash mark placed anywhere other
     than the first character of a line, will be considered part of a valid
     hostname or command.

DIAGNOSTICS
     Exit status is 0 on success, 1 if an error occurs.

SEE ALSO
     xterm(1), dsh(1), rvt(1), XSendEvent(3), kerberos(3), hosts.equiv(5),
     rhosts(5)

HISTORY
     The dvt command appeared in clusterit 2.0.

AUTHOR
     Dvt was written by Tim Rightnour.

BUGS
     Solaris 2.5.1 has a maximum of 256 open file descriptors.  This means
     that dvt will fail on a fanout size greater than about 32-40 nodes.

                                January 7, 2001
