tbswap.in 54.6 KB
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#!/usr/bin/perl -w

#
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# Copyright (c) 2000-2017 University of Utah and the Flux Group.
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# 
# {{{EMULAB-LICENSE
# 
# This file is part of the Emulab network testbed software.
# 
# This file is free software: you can redistribute it and/or modify it
# under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or (at
# your option) any later version.
# 
# This file is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public
# License for more details.
# 
# You should have received a copy of the GNU Affero General Public License
# along with this file.  If not, see <http://www.gnu.org/licenses/>.
# 
# }}}
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#
use English;

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# Returns 0 on success.
# Returns 1 on non-assign_wrapper failure.
# Returns (1 | assign_wrapper's errorcode) on assign_wrapper failure.
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# Returns |0x40 if update caused a swapout. Icky.
# Returns -1 on uncontrolled error (die called).
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# XXX: handle error cases for update? (backup the db?)
# XXX: Shouldn't do idempotent stuff twice for update.
# XXX: repush/calc routing for update??? (tbprerun)
# XXX: previz for update???              (tbprerun)
# XXX: make snmpit faster for update.
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#
# XXX: for update, expt is swapped out on os_setup fail.
#      (we only recover if assign fails)
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sub usage()
{
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    print STDERR
	"Usage: $0 {in|out|modify [-reboot] [-eventsys_restart]} ".
	"[-noswapout] [-genimode] pid eid\n";
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    exit(-1);
}

#
# Configure variables
#
my $TBROOT         = "@prefix@";
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my $TBOPS          = "@TBOPSEMAIL@";
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my $TBLOGS         = "@TBLOGSEMAIL@";
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my $MAINSITE	   = @TBMAINSITE@;
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my $ELABINELAB     = @ELABINELAB@;
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my $THISHOMEBASE   = "@THISHOMEBASE@";
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my $TESTMODE       = @TESTMODE@;
my $DISABLE_EVENTS = "@DISABLE_EVENT_SCHED@";
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my $mapper         = "$TBROOT/bin/mapper";
my $wrapper        = "$TBROOT/libexec/assign_wrapper";
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my $SNMPIT	   = "$TBROOT/bin/snmpit";
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my $RFLINKS	   = "$TBROOT/bin/rflinks";
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my $IMAGESETUP     = "$TBROOT/sbin/image_setup";
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my $portstats	   = "$TBROOT/bin/portstats";
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my $TCPP           = "$TBROOT/sbin/tcpp";
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my $NFSTRACESUPPORT= @NFSTRACESUPPORT@;
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my $PGENISUPPORT   = @PROTOGENI_SUPPORT@;
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# Untaint the path
$ENV{'PATH'} = "/usr/bin:$TBROOT/libexec:$TBROOT/libexec/ns2ir" . 
    ":$TBROOT/sbin:$TBROOT/bin";

#
# Testbed Support libraries
#
use lib "@prefix@/lib";
use libdb;
use libtestbed;
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use libadminctrl;
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use libadminmfs;
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use libtblog;
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use EmulabFeatures;
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use Experiment;
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use User;
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use Lan;
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use Firewall;
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#
# Actual swap-in and swap-out functions, defined below.
#
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sub doSwapout($);
sub doSwapin($);

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# XXX fixme: should not be hardwired!
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my $cnetstack = "-S Control";
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my $cnetvlanname = "Control";


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sub REAL()    { return 5; }
sub CLEANUP() { return 4; }
sub RETRY()   { return 3; }
sub MODIFY()  { return 2; }
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sub UPDATE()  { return 1; }
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sub MODIFY_RECOVER()  { return 0; }
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#
# Grab global enable of linkdelays.
#
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my $enablelinkdelays = TBGetSiteVar("general/linux_endnodeshaping");
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#
# Turn off line buffering on output
#

$| = 1;

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my $updateReboot   = 0;
my $updateReconfig = 1;
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my $update_Eventsys_restart = 0;
my $elabinelab     = 0;
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my $plabinelab     = 0;
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my $force          = 0;
my $noswapout      = 0;
my $genimode       = 0;
my $errors         = 0;
my $updatehosed    = 0;
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my $canceled;
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my $os_setup_pid;
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my $nextState;
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#
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# First argument is either "in", "out", or "update";
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# this value goes into $swapop.
#

my $swapop = shift;	

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if (!$swapop || 
    (($swapop ne "in") && 
     ($swapop ne "out") &&
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     ($swapop ne "modify") &&
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     ($swapop ne "update"))) {
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    usage();
}

#
# Get other arguments.
#

while ($#ARGV > 1) {
    $arg = shift;
    if ($arg eq "-force") {
	$force = 1;
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    } elsif ($arg eq "-reboot") {
	$updateReboot = 1;
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	$updateReconfig = 0;
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    } elsif ($arg eq "-noreconfig") {
	$updateReboot   = 0;
	$updateReconfig = 0;
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    } elsif ($arg eq "-eventsys_restart" && $swapop eq "modify") {
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	$update_Eventsys_restart = 1;
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    } elsif ($arg eq "-noswapout") {
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	$noswapout = 1;
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    } else {
	usage();
    }
}
if ($#ARGV < 1) {
    usage();
}
my ($pid,$eid) = @ARGV;

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#
# Untaint the arguments.
#
if ($pid =~ /^([-\@\w.]+)$/) {
    $pid = $1;
}
else {
    die("Tainted argument $pid!\n");
}
if ($eid =~ /^([-\@\w.]+)$/) {
    $eid = $1;
}
else {
    die("Tainted argument $eid!\n");
}

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#
# Set Error reporting info
# 
tblog_set_info($pid,$eid,$UID);

#
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# Turn on timestamps
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#
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TBDebugTimeStampsOn();

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#
# Verify user and get his DB uid and other info for later.
#
my $this_user = User->ThisUser();
if (! defined($this_user)) {
    tbdie("You ($UID) do not exist!");
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}
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my $user_uid   = $this_user->uid();
my $user_name  = $this_user->name();
my $user_email = $this_user->email();
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# Slowly convert to using Experiment module.
my $experiment = Experiment->Lookup($pid, $eid);
if (!defined($experiment)) {
    tbdie("Could not lookup experiment object!")
}

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# Do not reboot *or* reconfig the shared node experiment.
if (($swapop eq "modify" || $swapop eq "update") &&
    $pid eq TBOPSPID() &&
    ($eid eq "shared-nodes" || $eid eq "shared-node")) {
    $updateReboot   = 0;
    $updateReconfig = 0;
}

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#
# Print starting message.
#
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my $exptidx = $experiment->idx();
my $state   = $experiment->state();
my $group   = $experiment->GetGroup();
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print "Beginning swap-$swapop for $pid/$eid ($exptidx). " .
    TBTimeStampWithDate() . "\n";
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TBDebugTimeStamp("tbswap $swapop started");

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# Sanity check the current state. 
if (!$force) {
    if ($swapop eq "in") {
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	tbdie("Experiment should be ACTIVATING. Currently $state.")
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	    if ($state ne EXPTSTATE_ACTIVATING);
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    }
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    elsif ($swapop eq "out") {
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	tbdie("Experiment should be SWAPPING. Currently $state.")
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	    if ($state ne EXPTSTATE_SWAPPING);
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    }
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    elsif ($swapop eq "modify" || $swapop eq "update") {
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	tbdie("Experiment should be MODIFY_RESWAP. Currently $state.")
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	    if ($state ne EXPTSTATE_MODIFY_RESWAP);
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    }
}
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# Get elabinelab status. See below.
if (! TBExptIsElabInElab($pid, $eid, \$elabinelab)) {
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    tbdie("Could not get elabinelab status for experiment $pid/$eid");
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}
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# and plabinelab status.
if (! TBExptIsPlabInElab($pid, $eid, \$plabinelab)) {
    tbdie("Could not get plabinelab status for experiment $pid/$eid");
}
if ($elabinelab && $plabinelab) {
    tberror "Cannot get my head around Plab in Elab in Elab!\n";
    print "Failingly finished swap-$swapop for $pid/$eid. " .
	TBTimeStamp() . "\n";
    TBDebugTimeStamp("tbswap $swapop finished (failed)");
    exit(1);
}
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#
# See if we use the new version of SyncVlans.
#
my $syncvlans =
    (EmulabFeatures->FeatureEnabled("SyncVlans",
				    $this_user, $group, $experiment)
     || $pid eq "emulab-ops");

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#
# See if the experiment is firewalled
#
my $firewalled = TBExptFirewall($pid, $eid);

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#
# Do actual swapping
#
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if ($swapop eq "out") {
    #
    # Swap out
    #
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    tblog_set_attempt(1);
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    $errors = doSwapout(REAL);
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}
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elsif ($swapop eq "update" || $swapop eq "modify") {
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    #
    # Before swapout, do cursory admission control to see if the
    # modified experiment will be swappable. assign_wrapper does a
    # more stringent check using assign.
    #
    print STDERR "Checking with Admission Control ...\n";
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    if (! TBAdmissionControlCheck(undef, $experiment, undef)) {
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	tberror({type => 'secondary', severity => SEV_SECONDARY,
		 error => ['admission_control_failure']},
		"Admission control failure!\n");
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	print "Failingly finished swap-$swapop for $pid/$eid. " .
	    TBTimeStamp() . "\n";
	TBDebugTimeStamp("tbswap $swapop finished (failed)");
	exit(1);
    }
    
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    #
    # Update.
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    #
    tblog_set_attempt(1);

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    #
    # Phase One -- swap experiment partially out.
    #
    print STDERR "Backing up physical state...\n";
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    $experiment->BackupPhysicalState();
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    #
    # Actually, in update mode this is not done cause we are anticipating
    # adding nodes only.
    #
    $errors = ($swapop eq "modify" ? doSwapout(MODIFY) : 0);
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    if ($errors) {
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	#
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	# Clean up the mess, leaving the experiment in the SWAPPED state,
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	#
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	if ($noswapout || $elabinelab) {
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	    print STDERR "Leaving experiment swapped in as directed.\n";
	}
	else {
	    print STDERR "Cleaning up after errors.\n";
	    doSwapout(CLEANUP);
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	    $updatehosed = 1;
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	}
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    }
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    else {
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	#
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	# Phase Two -- swap experiment back in.
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	#
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	$errors = doSwapin(MODIFY);
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	if ($errors) {
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	    #
	    # There were errors; see if we can recover.
	    #
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	    my $CanRecover = 1;
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	    if ($errors != 7) {
		print STDERR "Update failure occurred _after_ assign phase; ";
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		$CanRecover = 0;
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	    }

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	    if ($CanRecover) {
		print STDERR "Recovering virtual and physical state.\n";

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		# It is safe to remove the phystate since we know it was
		# backed up above, and cause we do not know if assign_wrapper
		# made it to that point before it failed. 
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		if ($experiment->RemoveVirtualState() ||
		    $experiment->RestoreVirtualState() ||
		    $experiment->ReserveSharedBandwidth(1, 1) ||
		    $experiment->RemovePhysicalState() ||
		    $experiment->RestorePhysicalState()) {
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		    print STDERR "Could not restore backed-up state; ";
		    $CanRecover = 0;
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		}
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		else {
		    print STDERR "Doing a recovery swap-in of old state.\n";

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		    if (doSwapin(MODIFY_RECOVER)) {
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			print STDERR "Could not swap in old physical state; ";
			$CanRecover = 0;
		    }
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		}
	    }
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	    #
	    # Some part of the recovery failed; must swap it out. swapexp
	    # (caller) will then have to do more clean up, hence the special
	    # exit status indicated by $updatehosed.
	    # 
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	    if (!$CanRecover) {
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		if ($noswapout || $elabinelab) {
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		    print STDERR
			"No Recovery, but leaving experiment swapped in.\n";
		}
		else {
		    print STDERR
			"Recovery aborted! Swapping experiment out.\n";
		    doSwapout(CLEANUP);
		    $updatehosed = 1;
		}
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	    }
	    else {
		print STDERR "Update recovery successful.\n";
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	    }
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	}
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    }
}
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elsif ($swapop eq "in") {
    #
    # Swap in
    #
    my $retries = 2;
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    #
    # Before real swapin, do cursory admission control. assign_wrapper does
    # a more stringent check using assign.
    #
    print STDERR "Checking with Admission Control ...\n";
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    if (! TBAdmissionControlCheck(undef, $experiment, undef)) {
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	tberror({type => 'secondary', severity => SEV_SECONDARY,
		 error => ['admission_control_failure']},
		"Admission control failure!\n");
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	print "Failingly finished swap-$swapop for $pid/$eid. " .
	    TBTimeStamp() . "\n";
	TBDebugTimeStamp("tbswap $swapop finished (failed)");
	exit(1);
    }
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    tblog_set_attempt(1);
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    $errors = doSwapin(REAL);
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    #
    # Attempt a retry if: 
    #   a) there were errors, 
    #   b) doswapin() indicated (via return code 3) a retry is appropriate,
    #   c) we haven't tried too many times already.
    #   d) The cancelflag has not been set.
    #   e) $TESTMODE == 0.
    #
    while ($errors == 3 && $retries && !$canceled && !$TESTMODE) {
	$retries--;
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	tblog_inc_attempt();
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	print STDERR "Cleaning up after errors; will try again.\n";
	doSwapout(RETRY);
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	print STDERR "Trying again...\n";
	$errors = doSwapin(RETRY);
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    }
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    if ($errors || $canceled) {
	print STDERR "Cleaning up after " .
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	    ($canceled ? "cancelation" : "errors") . ".\n";
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	doSwapout(CLEANUP);
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    }
}

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tblog_set_attempt(0);

TBGetCancelFlag($pid, $eid, \$canceled);
if ($canceled) {
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    tberror ({type=>'summary', cause=>'canceled', 
	      severity=>SEV_IMMEDIATE, error=>['cancel_flag']},
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	     "Experiment swap-$swapop canceled by user.");
}

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#
# Write appropriate message and exit.
#
if ($errors) {
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    print "Failingly finished swap-$swapop for $pid/$eid. ".TBTimeStamp()."\n";
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    TBDebugTimeStamp("tbswap $swapop finished (failed)");
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    # Pass out magic value to indicate that update failed!
    exit(1 | ($updatehosed ? 0x40 : 0));
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}
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print "Successfully finished swap-$swapop for $pid/$eid. " .TBTimeStamp()."\n";
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TBDebugTimeStamp("tbswap $swapop finished (succeeded)");
exit(0);
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#################################

##
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#
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# doSwapout - Swaps experiment out.
#
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#             If in REAL or CLEANUP,
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#             this function will free all nodes for the 
#             experiment.
#
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#             If in RETRY or UDPATE,
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#             only nodes not in RES_READY will be freed.
#
#             Returns 0 on success, >0 on failure.
#
##

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sub doSwapout($) {
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    my $type = shift;
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    my $swapout_errors = 0;

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    tblog_set_cleanup(1) if $type == CLEANUP;

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    #
    # wait for os_setup;
    # this only applies if called after a failed doswapin.
    #
    if ($os_setup_pid) {
	print "Waiting for os_setup to finish\n";
	waitpid($os_setup_pid, 0);
	undef $os_setup_pid;
    }
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    if (0 && $NFSTRACESUPPORT && $type == REAL) {
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	print "Getting files accessed via NFS.\n";
	TBDebugTimeStamp("nfstrace started");
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	system("nfstrace transfer $pid $eid");
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	TBDebugTimeStamp("nfstrace finished");
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    }
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    if (! $TESTMODE) { 
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	if (! ($DISABLE_EVENTS || $elabinelab)) {
	    if ($type >= RETRY ||
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		($update_Eventsys_restart && $type == MODIFY) ) {
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		print "Stopping the event system\n";
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		if (system("eventsys_control stop $pid,$eid")) {
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		    tberror({type => 'secondary', severity => SEV_SECONDARY,
			     error => ['eventsys_stop_failed']},
			    "Failed to stop the event system.");
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		    $swapout_errors = 1;
		}
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	    }
	}
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	#
	# Do teardown of inner elab. We must do this before we teardown the
	# vlans since the inner control network is a vlan, and we want that
	# active so inner boss can reboot the inner nodes (avoid power cycle).
	#
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	if ($elabinelab && $type >= CLEANUP) {
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	    print "Tearing down elabinelab. This could take a while.\n";
	    if (system("elabinelab -k $pid $eid")) {
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		tberror({type => 'secondary', severity => SEV_SECONDARY,
			 error => ['elabinelab_tear_down_failed']},
			"Failed to teardown elabinelab!");
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		$swapout_errors = 1;
	    }
	}

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	#
	# Tear down TCP proxies.
	#
	if( $type != MODIFY ) {
	    print "Closing TCP proxy ports...\n";
	    if( system( "$TCPP -d $pid $eid" ) != 0 ) {
		tbwarn( "TCP proxy setup failed!" );
	    }
	}

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	if( $type >= CLEANUP ) {
	    print "Releasing public address pools...\n";
	    $experiment->ReleasePublicAddrPools();
	}

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	if( $type >= CLEANUP ) {
	    if( system( "$RFLINKS -r $pid $eid" ) ) {
		tbwarn( "Failed to remove RF links" );
	    }
	}
	
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	#
	# Grab our per-experiment switch stack name.
	#
	my @expswitches = $experiment->SwitchList(1);
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	my ($perexpstack,$leader,@curswitches) = 
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	    GetPerExperimentSwitchStack($experiment);
	my $stackarg = "";
	if (defined($perexpstack) && (@expswitches || @curswitches)) {
	    $stackarg = "-S $perexpstack --skip-supplied";
	}

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	#
	# Remove per-experiment switch stacks.
	#
	# Clean up any reserved VLAN tags in per-experiment switches so that
	# underlying logical wires can be deleted!
	#
	if ($type != MODIFY && defined($perexpstack)) {
	    # Kill tag reservations on actual swapout.
	    TBDebugTimeStamp("snmpit started");
	    print STDERR "Removing per-experiment VLANs.\n";
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	    if (system("$SNMPIT -S $perexpstack --redirect-err -r $pid $eid")) {
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		tbwarn "Failed to remove per-experiment VLANs";
	    }
	    TBDebugTimeStamp("snmpit finished");
	}
	if ($type >= RETRY && defined($perexpstack)) {
	    print STDERR "Removing per-experiment switch stack.\n";
	    DeletePerExperimentSwitchStack($experiment);
	    $stackarg = "";
	}

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	#
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	# Clean up any VLANs in experiment.
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	#
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	# When modifying an elabinelab experiment, leave the vlans intact
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	# so that the inner networks are not suddenly disconnected.
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	#
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	if ($type != MODIFY ||
	    ($type == MODIFY && $ELABINELAB && Lan->GotTrunks($experiment))) {
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	    # Kill tag reservations on actual swapout.
	    my $tagopt = ($type != MODIFY ? "-C" : "");
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	    TBDebugTimeStamp("snmpit started");
	    print STDERR "Removing VLANs.\n";
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	    if (system("$SNMPIT $stackarg --redirect-err $tagopt -r $pid $eid")) {
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		tberror({type => 'secondary', severity => SEV_SECONDARY,
			 error => ['vlan_reset_failed']},
			"Failed to reset VLANs");
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		$swapout_errors = 1;
	    }
	    TBDebugTimeStamp("snmpit finished");
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	}
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	#
	# Must check for stale vlans that we kept around in the above clause
	# since they will not be in the lans table anymore.
	#
	if ($type == CLEANUP) {
	    my @stale;
	    if (VLan->StaleVlanList($experiment, \@stale) != 0) {
		tberror({type => 'secondary', severity => SEV_SECONDARY,
			 error => ['vlan_reset_failed']},
			"Failed to get stale VLANs");
		$swapout_errors = 1;
	    }
	    if (@stale) {
		print "Removing stale vlans @stale\n";
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		system("$SNMPIT $stackarg --redirect-err -f -C ".
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                    join(" ", map("-o $_", @stale)));
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		if ($?) {
		    tberror({type => 'summary', severity => SEV_SECONDARY,
			     error => ['vlan_reset_failed']},
			    "Failed to remove stale vlans");
		    $swapout_errors = 1;
		}
	    }
	}
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    }
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    if ($type >= MODIFY) {
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	# XXX Do this before releasing the nodes. Needs more thought.
	$experiment->DeleteInternalProgramAgents();
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    }

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    if ($type >= RETRY) {
	print "Removing dynamic blobs.\n";
	$experiment->RemoveBlobs();
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	print "Clearing shared port vlans.\n";
	if ($experiment->ClearPortLans()) {
	    tberror({type => 'summary', severity => SEV_SECONDARY,
		     error => ['vlan_reset_failed']},
		    "Failed to remove ports from shared vlans");
	    #
	    # If this fails, we cannot release the nodes cause they
	    # have ports in someone elses vlan. Bad.
	    #
	    return -1;
	}
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    }

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    if ($type >= CLEANUP) {
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	#
	# Undo plab in elab specialness.
	# No need to worry about VLANs here, as all the special abilities
	# involve the control network.
	#
	if (! $TESTMODE && $plabinelab) {
	    print "Tearing down plabinelab.\n";
	    if (system("plabinelab -k $pid $eid")) {
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		tberror({type => 'secondary', severity => SEV_SECONDARY,
			 error => ['plabinelab_tear_down_failed']},
			"Failed to teardown plabinelab!");
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		$swapout_errors = 1;
	    }
	}

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	#
	# We're not attempting a retry;
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	#
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	# Stop all of the vnodes.
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	#
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	if (! $TESTMODE) { 	
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	    print "Tearing down virtual nodes.\n";
	    TBDebugTimeStamp("vnode_setup -k started");
	    if (system("vnode_setup -d -k $pid $eid")) {
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		tberror({type => 'secondary', severity => SEV_SECONDARY,
			 error => ['vnode_tear_down_failed']},
			"Failed to tear down vnodes.");
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		$swapout_errors = 1;
	    }
	    TBDebugTimeStamp("vnode_setup finished");
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	}

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	#
	# Nodes behind a firewall are treated special.
	# See undoFWNodes for details.
	#
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	# Non-firewalled experiments can now be paniced, and the swapout
	# action is similar. 
	#
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	if ($firewalled) {
	    if (undoFWNodes($experiment)) {
		tblog_set_cleanup(0);
		return 1;
	    }
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	}
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	elsif ($experiment->paniced() &&
	       Firewall::Panic($experiment, 0, Firewall::PANIC_ZAP())) {
	    return 1;
	}
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	#
	# Perform swapout time admin actions.  Right now there is at most
	# one of these.  It isn't really a general mechanism, just a hook
	# for state saving or data collection during swapout.
	# A couple of important "fer now" notes:
	#
	#	We don't do this for firewalled experiments.  We need a way
	#	to "tag" the saved disk state to ensure it doesn't get
	#	instantiated outside of a firewall.
	#
	#	We only do this on REAL swapouts, and not on CLEANUPs.
	#	There are some types of CLEANUPs where we may want to
	#	do this, in particular an invocation caused by a failed
	#	modify operation, where the admin action is to save the
	#	experiment state.  So we will need to revisit this.
	#
	my %soaction = ();
	if ($type == REAL && !$firewalled) {
	    TBExptGetSwapoutAction($pid, $eid, \%soaction);
	}
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	if ($soaction{'command'} && doSwapoutAction($pid, $eid, %soaction)) {
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	    tblog_set_cleanup(0);
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	    return 1;
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	}

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	#
	# Clear logical interfaces and wires. This might move to support
	# swapmod.
	#
	print "Removing logical wires.\n";
	if (Interface::Wire->DeleteLogicalWires($experiment)) {
	    tberror("Could not delete logical wires and interfaces\n");
	    return 1;
	}

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	#
	# remove all nodes from the experiment.
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	# (nfree will send them to RES_FREE_DIRTY)
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	#
	print STDERR "Freeing nodes.\n";
	TBDebugTimeStamp("nfree started");
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	if (system("nfree -a $pid $eid")) {
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	    tberror({type => 'secondary', severity => SEV_SECONDARY,
		     error => ['nfree_failed']},
		    "Could not free nodes.");
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	    $swapout_errors = 1;
	}
	TBDebugTimeStamp("nfree finished");
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	#
	# Since this is an actual swapout, 
	# reset our count of swap out nag emails sent.
	#
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	DBQueryWarn("update experiments set swap_requests='0', ".
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		    "   sim_reswap_count='0' ".
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		    "where eid='$eid' and pid='$pid'");
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    } else {
	#
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	# $type == RETRY or $type == MODIFY.
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	# Therefore, don't deallocate nodes which have been successfully
	# incorporated into the experiment (i.e., are RES_READY).
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	# (nfree will send deallocated nodes to RES_FREE_DIRTY)
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	#
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	my @failedpnodes = ();
	my @failedvnodes = ();
	
	my $db_result =
	    DBQueryFatal("select rv.node_id,n.allocstate,nt.isvirtnode ".
                         "  from reserved as rv ".
			 "left join nodes as n on n.node_id = rv.node_id ".
			 "left join node_types as nt on nt.type=n.type ".
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			 "where rv.pid='$pid' and rv.eid='$eid' and ".
			 "      rv.genisliver_idx is null");
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	while (my ($node,$allocstate,$isvirt) = $db_result->fetchrow_array) {
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	    if ($allocstate ne TBDB_ALLOCSTATE_RES_READY()) {
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		if ($isvirt) {
		    push(@failedvnodes, $node);
		}
		else {
		    push(@failedpnodes, $node);
		}
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	    }
	}

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	#
	# Tear down failed vnodes. Perhaps not needed?
	# 
	if (!$TESTMODE && @failedvnodes > 0) {
	    print "Tearing down failed virtual nodes.\n";
	    TBDebugTimeStamp("vnode_setup -k started");
	    if (system("vnode_setup -d -k $pid $eid @failedvnodes")) {
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		tberror({type => 'secondary', severity => SEV_SECONDARY,
			 error => ['vnode_tear_down_failed']},
			"Failed to tear down vnodes.");
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		$swapout_errors = 1;
	    }
	    TBDebugTimeStamp("vnode_setup -k finished");
	}
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	#
	# Undo plabinelab setup
	#
	if (!$TESTMODE && $plabinelab && @failedpnodes > 0) {
	    print "Removing failed nodes from inner plab.\n";
	    if (system("plabinelab -r $pid $eid @failedpnodes")) {
		tberror "Failed to remove inner nodes!";
		$swapout_errors = 1;
	    }
	}

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	#
	# Release all failed nodes.
	# 
	if (@failedpnodes > 0 || @failedvnodes > 0) {
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	    print STDERR "Freeing failed nodes.\n";
	    
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	    TBDebugTimeStamp("nfree started");
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	    #
	    # Specify -x switch so when a physical node gets freed,
	    # any virtual nodes (owned by this experiment)
	    # sitting on top of it are freed as well.
	    #
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	    if (system("nfree -x $pid $eid " .
		       join(" ", (@failedpnodes, @failedvnodes)))) {
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		tberror({type => 'secondary', severity => SEV_SECONDARY,
			 error => ['nfree_failed']},
			"Could not free nodes.");
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		$swapout_errors = 1;
	    }
	    TBDebugTimeStamp("nfree finished");
	}
    }

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    if (! $TESTMODE) {
	#
	# If the experiment has no Plab dslice nodes left, but still has
	# a Plab slice, destroy the slice
	#

	# Does the slice exist?
	$db_result =
	    DBQueryFatal("select slicename from plab_slices ".
			 "where pid='$pid' and eid='$eid'");

	if ($db_result->numrows) {
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	    # Are there any nodes left in the slice?
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	    $db_result =
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		DBQueryFatal("select r.node_id ".
			     " from plab_slices as ps".
			     " left join plab_slice_nodes as psn ".
			     "   on (ps.slicename=psn.slicename ".
			     "       and ps.plc_idx=psn.plc_idx) ".
			     " left join reserved as r ".
			     "   on psn.node_id=r.node_id ".
			     " where ps.pid='$pid' and ps.eid='$eid'".
			     "   and r.node_id is not NULL");
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	    if (!$db_result->numrows) {
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		print "Tearing down Slices.\n";
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		TBDebugTimeStamp("plabslice destroy started");
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		if (system("plabslice destroy $pid $eid")) {
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		    tberror "Failed to tear down Slices.";
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		    $swapout_errors = 1;
		}
		TBDebugTimeStamp("plabslice destroy finished");
	    }
	}
    }

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    if (! $TESTMODE) {
	#
	# All of these errors are non-fatal on swapout. We find out about them
	# via email sent from the individual scripts.
	#

	#
	# Only reset mountpoints if this is an actual swapout, and
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	# not a failed swapin(cleanup), update, or retry.
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	#
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	if ($type == REAL) {
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	    print "Resetting mountpoints.\n";
	    TBDebugTimeStamp("exports started");
	    if (system("exports_setup")) {
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		tberror({severity => SEV_WARNING,
			 error => ['mountpoint_reset_failed']},
			"Failed to reset mountpoints.");
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	    }
	    TBDebugTimeStamp("exports finished");
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	    print "Resetting locked down arp entries\n";
	    TBDebugTimeStamp("arplockdown started");
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	    if (system("arplockdown")) {
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		tberror({type => 'secondary', severity => SEV_SECONDARY,
			 error => ['arplockdown_setup_failed']},
			"Failed to reset locked down arp entries");
		return 1;
	    }
	    TBDebugTimeStamp("arplockdown finished");
    
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	    #
	    # Ditto these two. 
	    #
	    print "Resetting named maps.\n";
	    TBDebugTimeStamp("named started");
	    if (system("named_setup")) {
		tbwarn "Failed to reset named map.";
	    }
	    TBDebugTimeStamp("named finished");
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	    print "Resetting email lists.\n";
	    TBDebugTimeStamp("genelists started");
	    if (system("genelists -t")) {
		tbwarn "Failed to reset email lists.";
	    }
	    TBDebugTimeStamp("genelists finished");
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	}
    }

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    #
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    # Wipe the DB clean except during MODIFY or RETRY. In those
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    #    cases, assign_wrapper will reset the DB after reading
    #    the info.
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    #
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    if ( $type >= CLEANUP ) {
	print STDERR "Resetting DB.\n";
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	# Add purge flag.
	$experiment->RemovePhysicalState(1);
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	# Special. 
	$experiment->ClearPortRegistration();
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	$experiment->ClearPortRange();
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	$experiment->ClearGlobalIPAllocation();
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    }
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    tblog_set_cleanup(0);
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    return $swapout_errors;
}

##
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#
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# doSwapin - Swaps experiment in.
#
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#            Returns:
#              0 - successful swapin
#              1 - failed swapin; cleanup required.
#              3 - failed swapin; cleanup required; can retry.
#              7 - failed swapin; assign failed; no cleanup.
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##

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sub doSwapin($) {
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    my $type = shift; 
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    # Just the physnodes ...
    my @deleted_pnodes = ();
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    if ($type == REAL) {
	if ($experiment->CheckForDeprecatedImages($this_user, 1)) {
	    return 1;
	}
    }

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    # Special IP assignment. Must do before mapper runs and moves
    # IPs from virt_lans to interfaces table.
    if ($experiment->SetupNetworkFabrics()) {
	return 1;
    }

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    # Do this before we assign any nodes. We want to download the images.
    system("$IMAGESETUP -g $pid,$eid");
    if ($?) {
	return 1;
    }

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    #
    # assign_wrapper does all the virtual to physical mapping 
    # and updating the DB state.
    #
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    if ($type > MODIFY_RECOVER) {
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        #
        # Hacky test to allow disabling of linkdelays if the node is going
        # to run Linux. See sitevar above.
        #
	if (! $enablelinkdelays) {
	    $db_result =
		DBQueryFatal("select distinct e.pid,e.eid,vl.vnode,vn.osname ".
			 "  from experiments as e ".
			 "left join virt_lans as vl on vl.pid=e.pid and ".
			 "     vl.eid=e.eid ".
			 "left join virt_nodes as vn on vn.pid=e.pid and ".
			 "     vn.eid=e.eid and vn.vname=vl.vnode ".
			 "left join os_info as o on o.osname=vn.osname and ".
			 "  (o.pid=vl.pid or o.pid='" . TBOPSPID() . "') ".
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			 "left join os_info_versions as ov on ".
			 "     ov.osid=o.osid and ov.vers=o.version ".
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			 "where (vl.uselinkdelay!=0 or e.uselinkdelays!=0 or ".
			 "       e.forcelinkdelays!=0) and ".
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			 "     (ov.os is NULL or ov.os='Linux' or ".
			 "      ov.os='Fedora') and ".
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			 "     e.pid='$pid' and e.eid='$eid'");

	    if ($db_result->numrows) {
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		tberror "Endnodeshaping is disabled on Linux Images!";
		tberror "You must modify your experiment to swap it in.";
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		return 1;
	    }
	}
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        #
	# Check for feature to back off and let something else manage the
	# nodes in the experiment.  Unconditionally mark the experiment since
	# this feature is most likely to come from the swapper or project.
	# Need to do this before nalloc is called by the mapper.
        #
	if (EmulabFeatures->FeatureEnabled("ExternalNodeManagement",
					   $this_user,
					   $group,
					   $experiment)) {
	    TBDebugTimeStamp("ExternalNodeManagement feature is set.");
	    EmulabFeatures->Lookup("ExternalNodeManagement")->
		Enable($experiment);
	}
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	# Allocate public IP addresses now.  We do it early, because it's
	# very fast and might fail (it would be silly to go through all
	# the effort of mapping nodes only to later abort because we
	# didn't have enough public addresses).	
	print "Allocating public addresses...\n";
	if( $experiment->AllocatePublicAddrPools() < 0 ) {
	    tberror( "Failed to allocate public address pools!" );
	    return 1;
	}
	    	
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	print "Mapping to physical reality ...\n";
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	TBDebugTimeStamp("mapper wrapper started");
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	#
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	# Pass the -u (update) switch into assign_wrapper, which turns on
	# update mode. When doing a retry, must also fix the current nodes
	# to avoid stuff jumping around when simply trying to replace a node
	# that did not boot.
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	#
	my $exitcode;
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	my $cmd = "$mapper ";
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	if (EmulabFeatures->FeatureEnabled("OldMapper",
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					   $this_user, $group, $experiment)) {
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	    $cmd = "$wrapper";
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	}
	$cmd .= " -f"
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	    if ($type == RETRY);
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	if (system("$cmd -u $pid $eid")) {
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	    $exitcode = $? >> 8;

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	    tberror "Failed ($exitcode) to map to reality.";
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	    # Wrapper sets this bit when recoveryppxu is possible.
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	    if ($exitcode & 64) {
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		# We can recover. 
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		tbreport(SEV_SECONDARY, 'assign_wrapper_failed', $exitcode);
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		return 7;
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	    }
	    else {
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		# No recovery, no retry.
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		tbreport(SEV_SECONDARY, 'assign_wrapper_failed', $exitcode);
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		return 1;
	    }
	}
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	TBDebugTimeStamp("mapper wrapper finished");
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	print "Mapped to physical reality!\n";
    }
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    # Check cancel flag before continuing. No retry, 
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    TBGetCancelFlag($pid, $eid, \$canceled);
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    if ($canceled) {
	tbreport(SEV_IMMEDIATE, 'cancel_flag');
	return 1
    }
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    #
    # Create/update per-experiment switch stacks if necessary.
    # Still haven't done any vlan synch for modify.
    #
    my @expswitches = $experiment->SwitchList(1);
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    my ($perexpstack,$leader,@curswitches) = 
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	GetPerExperimentSwitchStack($experiment);
    my $stackarg = "";
    if (($type > MODIFY && @expswitches)
	|| ($type == MODIFY && (!defined($perexpstack) && @expswitches))) {
	print STDERR "Creating per-experiment switch stack.\n";
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	AddPerExperimentSwitchStack($experiment,undef,undef,undef,undef,
				    @expswitches);
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	$perexpstack = GetPerExperimentSwitchStackName($experiment);
    }
    elsif ($type == MODIFY && defined($perexpstack)
	   && (@expswitches || @curswitches)) {
	print STDERR "Updating per-experiment switch stack.\n";
	UpdatePerExperimentSwitchStack($experiment,@expswitches);
    }
    if (defined($perexpstack) && (@expswitches || @curswitches)) {
	print STDERR "Will configure per-experiment switch stack ($perexpstack) later.\n";
	$stackarg = "-S $perexpstack --skip-supplied";
    }

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    #
    # When doing a modify, we have to compare vlans to determine which
    # vlans actually changed and need to be deleted, before processing
    # the new vlans for the experiment. Note that vlans that already
    # exist on the switches will be left as is by snmpit.
    #
    # We must do this before the nfree of deleted nodes in the next section
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    # because the new test in nfree that prevents nodes from accidentally
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    # getting released when they are in a vlan.
    #
    if ($type == MODIFY) {
	my @diff = ();
	my @same = ();
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	my $ret;

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	if ($ELABINELAB || !$syncvlans) {
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	    $ret = Lan->CompareVlansWithSwitches($experiment, \@diff, \@same);
	}
	else {
	    $ret = Lan->CompareVlansWithSwitches2($experiment);