SPM(8) Domain/OS BSD SPM(8)
NAME
spm - start server process manager
SYNOPSIS
spm [-lo priority] [-hi priority]
DESCRIPTION
The Server Process Manager, spm, allows you to create a process on a node
remote from your own. On a Domain Server Processor (DSP), spm starts
when the operating system is loaded, and so it runs whenever the DSP is
on line. spm starts the mbx_helper program if it is not started on a DSP
from the `node_data/startup.spm file. Since they have no monitors or
keyboards, DSPs would be unusable without both of these server processes.
If spm starts up when a node is booted (i.e., if spm is running in
Process 1), it connects its standard streams (standard input, standard
output, and standard error) to the object `node_data/dev/sio.spm. This
object is generally a link which points to one of the sio lines (for
example, /dev/sio1), perhaps one to which a dumb terminal is connected.
The link may, however, point to the pathname of an existing log file, in
which case spm messages are written to that file. If there is any error
when spm opens `node_data/dev/sio.spm, then by default the standard
streams are connected to /dev/null.
Once spm is started you can:
Create processes from a remote node using the shell command crp with
options similar to the Display Manager's cpo and cps commands. The
process you create may run another server, such as prsvr or netman.
The process can also run a shell program.
Log in to the node for debugging purposes or to maintain servers.
For example, you might want to use the shell Command sigp to stop a
process (such as a print server) running on the node.
The spm process accepts the following commands from stdin:
help Displays the following three lines
SHUT [-Force] Shutdown the node
Quit Exit from spm to bootshell without cleanup
SHell Spawn a shell to login.
This can be useful, for example, when you have a dumb terminal attached
to one of the sio lines of a Domain Server Processor. When running in
this fashion, spm offers no prompt for command input.
Starting and Stopping spm
To start spm on your current node, use the DM command cps:
Command: cps /sys/spm/spm
The process begins immediately and continues after log out.
The spm process begins when the node is booted, and continues under
normal conditions until it is intentionally stopped with the shell
command shutspm issued in a process running on the remote node.
Once spm has started, it searches for the startup file
`node_data/startup.spm and executes any commands found therein. This is a
good place to put commands which create processes to run standard servers
such as the print server (prsvr).
Startup File Operations
The `node_data/startup.spm file may contain any or all of the following
commands:
Command Function
cpo pathname [options] Create background process (quits at logout)
cps pathname [options] Create server process (persists after logout)
env variable [value] Set environment variables
no_stdin Disable input from standard input
no_shutspm Disable spm shutdown via the shutspm command.
no_stdin and no_shutspm are commands recognized only by spm; they require
no arguments or options. cpo, cps, and env are DM commands; see their
individual help files for more details.
Controlling Access to a Node
spm can optionally prevent unauthorised users from creating processes on
a node or logging in. If the file `node_data/spm_control exists on the
node running spm, all process creation and login requests are validated
and only users with a SID matching an entry in the file are allowed
access. If the file does not exist all requests are allowed.
If present, the control file should contain a list of SIDs, one per line,
specifying users that are authorised. Each entry should be specified as
follows:
user.group.org
where a % character in a field matches anything.
Examples:
Allow access to all users
%.%.%
Allow access to all members of group grp
%.grp.%
OPTIONS
-low n Lower boundary priority of invoked processes.
-high n Upper boundary priority of invoked processes.
SEE ALSO
shutspm for information about stopping spm.
mbx_helper for details about the mailbox server.