node_reboot.in 17.9 KB
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#!/usr/bin/perl -wT
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#
# EMULAB-COPYRIGHT
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# Copyright (c) 2000-2004 University of Utah and the Flux Group.
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# All rights reserved.
#

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use English;
use Getopt::Std;

#
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# Reboot a node (or nodes). Will power cycle the node as a last resort.
# Use -e option to reboot all nodes in an experiment.
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#
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# Exit value is 0 if all nodes reboot okay, or the number of nodes
# could not be rebooted.
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#
sub usage()
{
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    print "Usage: node_reboot [-d] [-f] [-n] [-w] [-k] node [node ...]\n" .
	  "       node_reboot [-d] [-f] [-n] [-w] [-k] -e pid,eid\n".
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	"Use the -d option to turn on debugging\n" .
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	"Use the -e option to reboot all the nodes in an experiment\n" .
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	"Use the -n option to not wait for nodes to go down\n" .
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	"Use the -w option to to wait for nodes is come back up\n" .
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	"Use the -k option to power cycle nodes in PXEWAIT mode\n" .
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	"Use the -a option to reboot all free nodes\n".
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	"Use the -f option to power cycle (and not wait for nodes to die)\n";
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    exit(-1);
}
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# The hidden -r option runs this in "realmode", ie don't send an event, but
# really do the work instead.
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my  $optlist = "dfe:nwrka";
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#
# Configure variables
#
my $TB		= "@prefix@";
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my $CLIENT_BIN  = "@CLIENT_BINDIR@";
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my $BOSSNODE    = "@BOSSNODE@";
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#
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# Testbed Support libraries
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#
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use lib "@prefix@/lib";
use libdb;
use libtestbed;
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use event;
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use POSIX qw(strftime);
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my $ssh		= "$TB/bin/sshtb -n";
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my $power	= "$TB/bin/power";
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my $ipod	= "$TB/sbin/apod";
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my $vnodesetup	= "$TB/sbin/vnode_setup";
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my $bisend      = "$TB/sbin/bootinfosend";
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my $logfile	= "$TB/log/power.log";
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my $ping	= "/sbin/ping";
my %pids	= ();
my @row;
my @nodes       = ();
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my $debug       = 0;
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my $force       = 0;
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my $waitmode    = 0;
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my $realmode    = 0;
my $nowait      = 0;
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my $failed      = 0;
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my $eidmode     = 0;
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my $killmode    = 0;
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my $freemode    = 0;
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my $batchcount  = 12;
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my $pid;
my $eid;
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# un-taint path
$ENV{'PATH'} = '/bin:/sbin:/usr/bin:/usr/local/bin';
delete @ENV{'IFS', 'CDPATH', 'ENV', 'BASH_ENV'};

# Turn off line buffering on output
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$| = 1;
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#
# We don't want to run this script unless its the real version.
#
if ($EUID != 0) {
    die("Must be root! Maybe its a development version?");
}

#
# Parse command arguments. Once we return from getopts, all that should
# left are the required arguments.
#
%options = ();
if (! getopts($optlist, \%options)) {
    usage();
}
if (defined($options{"d"})) {
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    $debug = 1;
}
if (defined($options{"f"})) {
    $force = 1;
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}
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if (defined($options{"k"})) {
    $killmode = 1;
}
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if (defined($options{"w"})) {
    $waitmode = 1;
}
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if (defined($options{"r"})) {
    $realmode = 1;
}
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if (defined($options{"a"})) {
    $freemode = 1;
}
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if (defined($options{"n"}) && !defined($options{"w"})) {
    $nowait = 1;
}
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if (defined($options{"e"})) {
    if (@ARGV) {
	usage();
    }
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    $eidmode = $options{"e"};
    if ($eidmode =~ /([-\w]*),([-\w]*)/) {
	$pid = $1;
	$eid = $2;
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    }
    else {
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	print STDOUT "Invalid argument to -e option: $eidmode\n";
	usage();
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    }
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}

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# XXX Temporary, until we make event sending the default
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$realmode=1;
#if ($realmode && $UID && !TBAdmin($UID)) {
#    die("*** You cannot use real mode!\n");
#}
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if ($freemode) {
    #
    # Reboot all free nodes
    #
    if ($UID && !TBAdmin($UID)) {
	die("*** You not have permission to reboot all free nodes!\n");
    }

    my $query_result =
	DBQueryFatal("select n.node_id from nodes as n ".
		     "left join reserved as r on r.node_id=n.node_id ".
		     "left join node_types as nt on nt.type=n.type ".
		     "where nt.class='pc' and n.role='testnode' and ".
		     "      r.pid is NULL");

    if ($query_result->numrows == 0) {
	print STDOUT "There are no free nodes to reboot\n";
	usage();
    }
    
    while (@row = $query_result->fetchrow_array()) {
	push(@nodes, $row[0]);
    }
}
elsif ($eidmode) {
    #
    # If eidmode, then get the node list out of the DB instead of the command
    # line. A proper check is made later, so need to be fancy about the query.
    #
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    my @row;
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    #
    # Verify permission to muck with this experiment.
    #
    if ($UID && !TBAdmin($UID) &&
	! TBExptAccessCheck($UID, $pid, $eid, TB_EXPT_MODIFY)) {
	die("*** You not have permission to reboot nodes in $pid/$eid!\n");
    }
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    my $query_result =
	DBQueryFatal("select node_id from reserved where ".
		     "pid='$pid' and eid='$eid'");

    if ($query_result->numrows == 0) {
	print STDOUT "There are no nodes reserved in pid/eid $pid/$eid\n";
	usage();
    }
    while (@row = $query_result->fetchrow_array()) {
	push(@nodes, $row[0]);
    }
}
else {
    if (@ARGV == 0) {
	usage();
    }
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    # Untaint the nodes.
    foreach my $node ( @ARGV ) {
	if ($node =~ /^([-\@\w]+)$/) {
	    $node = $1;
	}
	else {
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	    die("Bad node name: $node\n");
	}
	if (!TBValidNodeName($node)) {
	    die("Node does not exist: $node\n");
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	}
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	push(@nodes, $node);
    }
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    #
    # Verify permission to reboot these nodes.
    #
    if ($UID && !TBAdmin($UID) &&
	! TBNodeAccessCheck($UID, TB_NODEACCESS_REBOOT, @nodes)) {
	die("You do not have permission to reboot one (or more) ".
	    "of the nodes!\n");
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    }
}

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#
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# VIRTNODE HACK: Virtual nodes are special. We can reboot jailed vnodes.
# but not old style (non-jail). Also, if we are going to reboot the physical
# node that a vnode is on, do not bother with rebooting the vnode since
# it will certainly get rebooted anyway!
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#
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my %realnodes = ();
my %virtnodes = ();

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foreach my $node ( @nodes ) {
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    my ($jailed, $plab);
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    if (TBIsNodeVirtual($node, \$jailed, \$plab)) {
	if (! $jailed && ! $plab) {
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	    print "*** Skipping old style (non-jail) virtual node $node ...\n";
	    next;
	}
	my $pnode;
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	if (! TBPhysNodeID($node, \$pnode)) {
	    die("*** $0:\n".
		"    No physical node for $node!\n");
	}
	$virtnodes{$node} = $pnode;
    }
    else {
	$realnodes{$node} = $node;
    }
}
for my $node ( keys(%virtnodes) ) {
    my $pnode = $virtnodes{$node};

    if (defined($realnodes{$pnode})) {
	print "*** Dropping $node since its host ($pnode) will reboot ...\n";
	delete($virtnodes{$node});
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    }
}
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if (! keys(%realnodes) && ! keys(%virtnodes)) {
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    print "No nodes to reboot. Exiting ...\n";
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    exit(0);
}

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#
# By here we've done all the preliminaries... send the event, unless we're
# in realmode.
#

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my @sortednodes = sort(keys(%realnodes));
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if (!$realmode) {
    EventSendFatal(host      => $BOSSNODE ,
		   objtype   => TBDB_TBEVENT_COMMAND ,
		   eventtype => TBDB_COMMAND_REBOOT ,
		   objname   => join(",",@sortednodes) );
    if (!$nowait) {
	# In here we can do some output to tell the user what's going on.
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	if ($waitmode) {
	    # Wait for [SHUTDOWN,ISUP]

	} else {
	    # Wait for [SHUTDOWN]

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	}
    }
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    exit(0);
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}

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#
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# Another shark hack. Well, perhaps not. We really don't want 50 nodes
# all rebooting at the same time, PCs *or* sharks. Lets order them
# so that the shelves are grouped together at least, and issue the reboots
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# in batches.
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#
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while (@sortednodes) {
    my @batch = ();
    my $i     = 0;
    my $lastshelf = 0;
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    while ($i < $batchcount && @sortednodes > 0) {
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	my $node = shift(@sortednodes);
	my $shelf;
	my $unit;

	#
	# The point of this sillyness is stop at each shelf transition.
	#
	if (IsShelved($node, \$shelf, \$unit)) {
	    if ($lastshelf && $lastshelf ne $shelf) {
		unshift(@sortednodes, $node);
		last;
	    }
	    $lastshelf = $shelf;
	}
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	push(@batch, $node);
	$i++;
    }

    if ($force) {
        #
        # In force mode, call the power program for the whole batch, and
	# continue on. We don't wait for them to go down or reboot.
        #
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	info("Force mode: power cycle ".join(" ",@batch));
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	PowerCycle(@batch);
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	if ($?) {
	    exit ($? >> 8);
	}
    }
    else {
        #
        # Fire off a reboot process so that we can overlap them all.
        # We need the pid so we can wait for them all before preceeding.
        #
	foreach my $node ( @batch ) {
	    $mypid = RebootNode($node);
	    $pids{$node} = $mypid;
	}
    }

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    #
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    # If there are more nodes to go, then lets pause a bit so that we
    # do not get a flood of machines coming up all at the same exact
    # moment.
    #
    if (@sortednodes) {
	print STDOUT "Pausing to give some nodes time to reboot ...\n";
	if ($lastshelf) {
	    sleep(15);
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	} else {
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	    sleep(10);
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	}
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    }
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}

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#
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# Wait for all the reboot children to exit before continuing.
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#
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my @needPowercycle = ();
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if (! $force) {
    foreach my $node ( sort(keys(%realnodes)) ) {
	my $mypid     = $pids{$node};
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	my $status;
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	#
	# Child may have avoided the fork, and returned status directly.
	# Flip it and apply the same test.
	#
	if ($mypid <= 0) {
	    $status = -$mypid;
	}
	else {
	    waitpid($mypid, 0);
	    $status = $? >> 8;
	}
	
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	if ($status == 2) {
	    # Child signaled to us that this node needs a power cycle
	    push @needPowercycle, $node;
	} elsif ($?) {
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	    $failed++;
	    print STDERR "Reboot of node $node failed!\n";
	}
	else {
	    print STDOUT "$node rebooting ...\n";
	}
    }
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}

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#
# Power cycle nodes that couldn't be brought down any other way
#
if (@needPowercycle) {
    PowerCycle(@needPowercycle);
}

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#
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# Now do vnodes. Do these serially for now (simple).
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#
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for my $node ( keys(%virtnodes) ) {
    my $pnode = $virtnodes{$node};
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    if (RebootVNode($node, $pnode)) {
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	$failed++;
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	print STDERR "Reboot of node $node on $pnode failed!\n";
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    }
    else {
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	print STDOUT "$node on $pnode rebooting ...\n";
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    }
}

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if ($failed) {
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    print STDERR "$failed real nodes could not be rebooted\n";
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    exit($failed);
}

#
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# Wait for nodes to reboot. We wait only once, no reboots.
#
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if ($waitmode) {
    my $waitstart = time;

    print STDOUT "Waiting for nodes to come up ...\n";

    # Wait for events to filter through stated! If we do not wait, then we
    # could see nodes still in ISUP.
    sleep(2);
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    foreach my $node ( sort(@nodes) ) {
	if (!TBNodeStateWait($node, TBDB_NODESTATE_ISUP, $waitstart, (60*6))) {
	    print STDOUT "$node is alive and well\n";
	    SetNodeBootStatus($node, NODEBOOTSTATUS_OKAY);
	    next;
	}
	SetNodeBootStatus($node, NODEBOOTSTATUS_FAILED);
	$failed++;
    }
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}
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print "Done. There were $failed failures to reboot.\n";
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exit $failed;

#
# Reboot a node in a child process. Return the pid to the parent so
# that it can wait on all the children later.
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#
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sub RebootNode {
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    my ($pc) = @_;
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    my ($status, $syspid, $mypid, $didipod, $nodestate);
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    print STDOUT "Rebooting $pc ...\n";

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    # Report some activity into last_ext_act
    TBActivityReport($pc);

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    #
    # Is the node in PXEWAIT? If so we want to wake it up so that it can
    # query bootinfo and do what it is supposed to do, without a real reboot.
    # We send the initial wakeup from here, but let stated deal with it
    # failing (timeout) and resending it. That means we could be called
    # with the node in PXEWAKEUP, so send it another wakeup. The point is that
    # stated is controlling the timeouts. Eventually stated gives up and uses
    # the -k option to force a power cycle.
    #
    if (! TBGetNodeEventState($pc, \$nodestate)) {
	info("$pc has no event state: power cycle");
	print STDERR "$pc has no event state Power cycling ...\n" if $debug;
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	# Signal to the called that the node needs to be power cycled
	return -2;
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    }
    if ($nodestate eq TBDB_NODESTATE_PXEWAIT() ||
	$nodestate eq TBDB_NODESTATE_PXEWAKEUP()) {
	#
	# In killmode, we do not want to bother with sending a wakeup event.
	# Just do the power cycle. This is used to unstick a machine that
	# is in waitmode, but not responding to the wakeups. 
	#
	if ($killmode) {
	    info("$pc: in $nodestate: but power cycling in killmode");
	    print STDERR "$pc: in $nodestate: but power cycling in killmode\n"
		if $debug;
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	    # Signal to the caller that the node needs to be power cycled
	    return -2;
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	}
	
	#
	# The aux program sends the event to stated ...
	#
	my $optarg = ($debug ? "-dd" : "");
	    
	print STDERR "$pc: in $nodestate: sending wakeup command.\n" if $debug;
	system("$bisend $optarg -q $pc");
	if ($?) {
	    info("$pc: PXEWAKEUP failed ... power cycle");
	    print STDERR "$pc: PXEWAKEUP failed ... power cycle.\n" if $debug;
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	    # Signal to the caller that the node needs to be power cycled
	    return -2;
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	}
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	return 0;
    }

    #
    # Do the rest in a child process. After the fork, we do the ping test
    # before we reconnect to the DB. This cuts down on the flurry of connects
    # by a bunch of children (ping will take a moment to run). 
    #
    $mypid = fork();
    if ($mypid) {
	return $mypid;
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    }

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    #
    # See if the machine is pingable. If its not pingable, then we just
    # power cycle the machine rather than wait for ssh to time out.
    #
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    if (! DoesPing($pc)) {
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	info("$pc appears dead: power cycle");
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	print STDERR "$pc appears to be dead. Power cycling ...\n" if $debug;
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	# Signal to the parent that the node needs to be power cycled
	exit(2);
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    }
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    TBdbfork();
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    #
    # Machine is pingable at least. Try to reboot it gracefully,
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    # or power cycle anyway if that does not work.
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    #
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    print STDERR "Trying ssh reboot of $pc ...\n" if $debug;
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    #
    # Must change our real UID to root so that ssh will work. We save the old
    # UID so that we can restore it after we finish the ssh
    #
    my $oldUID = $UID;
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#    print STDERR "Saved UID: $oldUID\n" if $debug;
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    $UID = 0;
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    #
    # Run an ssh command in a child process, protected by an alarm to
    # ensure that the ssh is not hung up forever if the machine is in
    # some funky state.
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    #
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    $syspid = fork();
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    if ($syspid) {
	local $SIG{ALRM} = sub { kill("TERM", $syspid); };
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	alarm 20;
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	waitpid($syspid, 0);
	alarm 0;

	#
	# The ssh can return non-zero exit status, but still have worked.
	# FreeBSD for example.
	#
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	print STDERR "reboot of $pc returned $?.\n" if $debug;
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	#
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	# If either ssh is not running or it timed out,
	# send it a ping of death.
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	#
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	if ($? == 256 || $? == 15) {
	    if ($? == 256) {
		print STDERR "$pc is not running sshd.\n" if $debug;
	    } else {
		print STDERR "$pc is wedged.\n" if $debug;
	    }
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	    info("$pc: ssh reboot failed ... sending ipod");
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	    print STDERR "Trying Ping-of-Death on $pc ...\n" if $debug;

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	    system("$ipod $pc");
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	    $didipod = 1;
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	} else {
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	    info("$pc: ssh reboot ($?)");
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	    $didipod = 0;
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	}
    }
    else {
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	exec("$ssh -host $pc /sbin/reboot");
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	exit(0);
    }

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    #
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    # Restore the old UID so that scripts run from this point on get the
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    # user's real UID
    #
    $UID = $oldUID;
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#    print STDERR "Restored UID: $UID\n" if $debug;
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    #
    # Okay, before we power cycle lets really make sure. We wait a while
    # for it to stop responding to pings, and if it never goes silent,
    # punch the power button.
    #
    if (WaitTillDead($pc) == 0) {
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	my $state = TBDB_NODESTATE_SHUTDOWN;
	TBSetNodeEventState($pc,$state);
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	exit(0);
    }
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    #
    # Haven't yet tried an ipod, try that and wait again.
    # This further slows down reboot but is probably worth it
    # since this should be a rare case (reboot says it worked but
    # node doesn't reboot) and is vital if the nodes have no
    # power cycle capability to fall back on.
    #
    if (! $didipod) {
	info("$pc: reboot failed ... sending ipod");
	$UID = 0;
	system("$ipod $pc");
	$UID = $oldUID;
	if (WaitTillDead($pc) == 0) {
	    my $state = TBDB_NODESTATE_SHUTDOWN;
	    TBSetNodeEventState($pc,$state);
	    exit(0);
	}
    }

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    info("$pc: ipod failed ... power cycle");
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    print STDERR "$pc is still running. Power cycling ...\n" if $debug;
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    exit(2);
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}

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#
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# Reboot a vnode in a child process, and wait for it.
#
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sub RebootVNode($$) {
    my ($vnode, $pnode) = @_;
    my $syspid;

    print STDOUT "Rebooting $vnode on $pnode ...\n";

    #
    # Run an ssh command in a child process, protected by an alarm to
    # ensure that the ssh is not hung up forever if the machine is in
    # some funky state.
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    #
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    $syspid = fork();

    if ($syspid) {
	local $SIG{ALRM} = sub { kill("TERM", $syspid); };
	alarm 20;
	waitpid($syspid, 0);
	alarm 0;
	my $exitstatus = $?;

	#
	# The ssh can return non-zero exit status, but still have worked.
	# FreeBSD for example.
	#
	print STDERR "reboot of $vnode returned $exitstatus.\n" if $debug;
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	#
	# Look for setup failure, reported back through ssh.
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	#
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	if ($exitstatus) {
	    if ($exitstatus == 256) {
		print STDERR "$pnode is not running sshd.\n" if $debug;
	    }
	    elsif ($exitstatus == 15) {
		print STDERR "$pnode is wedged.\n" if $debug;
	    }
	}
	return($exitstatus);
    }
    #
    # Must change our real UID to root so that ssh will work.
    #
    $UID = 0;
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    exec("$ssh -host $vnode $CLIENT_BIN/vnodesetup -r -j $vnode");
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    exit(0);
}

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#
# Power cycle a PC using the testbed power program.
#
sub PowerCycle {
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    my @pcs = @_;

    my $pcstring = join(" ",@pcs);
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    system("$power cycle $pcstring");
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    return $? >> 8;
}

#
# Wait until a machine stops returning ping packets.
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#
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sub WaitTillDead {
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    my ($pc) = @_;
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    print STDERR "Waiting for $pc to die off\n" if $debug;
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    #
    # Sigh, a long ping results in the script waiting until all the
    # packets are sent from all the pings, before it will exit. So,
    # loop doing a bunch of shorter pings.
    #
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    for ($i = 0; $i < 30; $i++) {
	if (! DoesPing($pc)) {
	    print STDERR "$pc is rebooting.\n" if $debug;
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	    return 0;
	}
    }
    print STDERR "$pc is still alive.\n" if $debug;
    return 1;
}

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#
# Returns 1 if host is responding to pings, 0 otherwise
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# This routine is NOT allowed to do any DB queries! 
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#
sub DoesPing {
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    my ($pc) = @_;
    my $status;
    my $saveuid;
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    $saveuid = $UID;
    $UID = 0;
    system("$ping -q -i 0.25 -c 8 -t 2 $pc >/dev/null 2>&1");
    $UID = $saveuid;
    $status = $? >> 8;

    #
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    # Ping returns 0 if any packets are returned. Returns 2 if pingable
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    # but no packets are returned. Other non-zero error codes indicate
    # other problems.  Any non-zero return indicates "not pingable" to us.
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    #
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    print STDERR "$ping $pc returned $status\n" if $debug;
    if ($status) {
	return 0;
    }
    return 1;
}
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sub info($) {
    my $message = shift;
    # Print out log entries like this:
    # Sep 20 09:36:00 $message
    open(LOG,">> $logfile");
    print LOG strftime("%b %e %H:%M:%S",localtime)." $message\n";
    close(LOG);
}
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