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scout

SCore parallel shell. More...

Scout is an environment for executing shell command on every host in a cluster.

SYNOPSIS

scout [OPTIONS] -g GROUP
scout [OPTIONS] COMMAND ...
scout

The first form of the SCOUT invokation is to create a SCOUT environment. The second form of invokation is to run the shell commands on compute hosts in parallel. The third form of invokation is used to determine if the current einvironment is already in a SCOUT environment or not.
When a SCOUT environment is created, a new shell is created. To exit a SCOUT environment, terminate the shell.

Parameters:

	GROUP	group name to specify the set of compute hosts (see scorehosts(1)).
	COMMAND	any shell command and associated arguments if any.

OPTIONS for CREATING SCOUT ENVIRONMENT

-force

Force to create new SCOUT environment while in a SCOUT environment already

-X

Enables X11 forwarding.

-rsh RSH

Specify the remote shell command name or path to spawn remote process. See allso the SCORE_RSH environment description below.

-timeout SEC

Specify the timeout duration (in seconds) while invoking remote processes.

OPTIONS WITHIN SCOUT ENVIRONMENT

-merge

Merge same output of command execution on each compute node (default).

-sort

Sort alphabetically output of command execution on each compute node

-rev

Reverse-sort alphabetically output of command execution on each compute node

-nosort

Do not sort nor merge output of command execution on each compute node

-stdin

Run command on compute nodes with the standard input (STDIN, see below).

-catwalk DIRS

Enables on-deman file staging system, Catwalk. The DIRS is the colon (:) separated list of directory names from where files should be copied into the current directory of compute nodes, when the files do not exist on the compute nodes. And when the command terminates, newly created files or stage-in files but modified in the current directory of the compute nodes are copied back to the current directory of the local (server) node. When the filename opened by the command includes one or more slash (/) character(s), then the catwalk ignores the file and nothing special happens. For further details, see catwalk(7).

STANDARD INPUT

When the scout command is invoked with the -stdin option, the standard input of the local scout command is broadcasted to the remote processes in a parallel way. The following example shows how a local file is copied into every compute hosts.

	% scout -g HOSTGROUP
	% scout -stdin "cat > /tmp/remote-file" < ./local-file

Here, the copy of ./local-file is created on every remote hosts. Note that the remote shell command must be quoted so that the local shell will not interpret it.

ENVIRONMENT

SCBDSERV

Scoreboard server or the path to the scorehosts.db file.

DISPLAY

The DISPLAY environment variable indicates the location of the X11 server. To use X11 in the SCOUT environment, combine with the -X option described above.

SCORE_RSH

Specify the remote shell command name or path to spawn remote process. If the -rsh option is specified then this variable is ignored. ssh(1) can also be specified for the SCORE_RSH environment or the -rsh option value, however, ssh(1) must be setup to enable the agent forwarding, and the -A option of the ssh(1) command will not work.