HBOOT(1)							     LAM TOOLS								  HBOOT(1)

NAME

       hboot - Start LAM on the local node.

SYNOPSIS

       hboot [-dhstvNV] [-c conf] [-I inet_topo] [-R rtr_topo]

OPTIONS

       -d	       Turn on debugging.  This implies -v.

       -h	       Print the command help menu.

       -s	       Close stdio of child processes.

       -t	       Terminate (tkill(1)) any previous LAM session before starting.

       -v	       Be verbose.

       -N	       Go through the motions but do not actually take any action.

       -V	       Format and print the process schema.

       -c conf	       Use conf as the process schema.

       -I inet_topo    Set the $inet_topo variable in the process schema.

       -R rtr_topo     Set the $rtr_topo variable in the process schema.

DESCRIPTION

       Most MPI users will probably not need to use the hboot command; see lamboot(1).

       The  hboot  tool can be understood as a generic utility that starts multiple processes on the local node, based on information in a process
       schema.	It is not restricted to starting LAM.  It is part of the startup sequence preformed by lamboot(1).

       A process schema is a description of the processes which constitute the operating system on a given node.  Naturally,  the  process  schema
       used by hboot should be the one that describes LAM on a node.  The grammar of the process schema is described in conf(5).

       When starting LAM on a remote machine using rsh(1), the open file descriptors of the processes started by hboot must be closed in order for
       rsh(1) to exit.	This is done by using the -s option.  The -t option can be used to force a tkill(1) on the machine  before  attempting	to
       start LAM.  This feature is used by lamboot(1) to handle the case where a user might start a machine a second time without using lamwipe(1)
       to terminate the previous LAM session.

       The -I and -R options set their respective variables to the given values.  The $inet_topo variable is typically used by	the  LAM  Internet
       datalinks that communicate with other nodes.  The $rtr_topo variable is passed to the LAM router that handles network and topology informa-
       tion.  The variables can also be set in the process schema file (see conf(5)) but their values are overridden by the command line options.

       When LAM is started, the kernel records all processes that attach to it, including all the processes in the process schema.  It is the  job
       of tkill(1) to use this information to remove these processes from the node.

EXAMPLES

       hboot -v
	   Start LAM on the local node with the default process schema.  Report about every step as it is done.

       hboot -c myconfig
	   Boot the local node with the custom process schema, myconfig.

FILES

       laminstalldir/etc/lam-conf.lamd
				     default node process schema, where "laminstalldir" is the directory where LAM/MPI was installed

       laminstalldir/etc/lam7.1.4helpfile
				     Default location for help file for diagnostic messages that hboot may generate.

       /tmp/lam-$USER@hostname	     kill file for the LAM session on machine hostname, where $USER is the userid.

DIAGNOSTICS

       Using  ps(1) after hboot will display, among others, the LAM processes that have been started.  They may be killed one by one with kill(1),
       or all at once by killing the LAM kernel process with a HUP signal.  The preferred method is to use the LAM tool tkill(1) which should kill
       them  all at once, and also remove the kill file.  New users should make liberal use of ps(1) to gain confidence that the system is working
       properly.  In a disaster, ps(1) and kill(1) are your only hope of recovery.

SEE ALSO

       lamboot(1), tkill(1), conf(5), lam-helpfile(5)

LAM 7.1.4							    July, 2007								  HBOOT(1)