diff --git a/tools/runtime/sflow/sflow-to-rrd-handler b/tools/runtime/sflow/sflow-to-rrd-handler
index af39c0b78..fa1311dd9 100755
--- a/tools/runtime/sflow/sflow-to-rrd-handler
+++ b/tools/runtime/sflow/sflow-to-rrd-handler
@@ -2,7 +2,7 @@
 #
 # sflow-to-rrd-handler
 #
-# Copyright (C) 2009 - 2019 Internet Neutral Exchange Association Company Limited By Guarantee.
+# Copyright (C) 2009 - 2025 Internet Neutral Exchange Association Company Limited By Guarantee.
 # All Rights Reserved.
 #
 # This file is part of IXP Manager.
@@ -36,16 +36,21 @@ use Time::HiRes qw(ualarm gettimeofday tv_interval);
 use JSON;
 use REST::Client;
 
+use threads;
+
 use FindBin qw($Bin);
 use File::Spec;
 use lib File::Spec->catdir( $Bin, File::Spec->updir(), File::Spec->updir(), 'perl-lib', 'IXPManager', 'lib' );
 
 use IXPManager::Config;
 
-my $ixp = new IXPManager::Config (dbase_disable => 1);	# (configfile => $configfile);
+my $ixp = new IXPManager::Config;	# (configfile => $configfile);
+my $dbh = $ixp->{db};
 
 my $debug = defined($ixp->{ixp}->{debug}) ? $ixp->{ixp}->{debug} : 0;
 my $insanedebug = 0;
+my $map_vlans = defined($ixp->{ixp}->{map_vlans}) ? $ixp->{ixp}->{map_vlans} : 0;
+my $map_vlan_query = $ixp->{ixp}->{map_vlan_query};
 my $rrdcached = defined($ixp->{ixp}->{sflow_rrdcached}) ? $ixp->{ixp}->{sflow_rrdcached} : 1;
 my $sflowtool = defined($ixp->{ixp}->{sflowtool}) ? $ixp->{ixp}->{sflowtool} : '/usr/bin/sflowtool';
 my $sflowtool_opts = defined($ixp->{ixp}->{sflowtool_opts}) ? $ixp->{ixp}->{sflowtool_opts} : '-l';
@@ -59,6 +64,7 @@ my $daemon = 1;
 my $infraid = undef;
 my $macdbtype = defined($ixp->{ixp}->{macdbtype}) ? $ixp->{ixp}->{macdbtype} : '';
 my $macdbrest;
+my $vlan_mappings;
 
 # conundrum: do we run GetOptions() before creating a new IXPManager::Config
 # object, which would allow us to set the configfile location on the command
@@ -106,10 +112,17 @@ my $mactable = reload_mactable($client, $macdbrest);
 $mactable || die "FATAL: could not read IXP Manager API call on $apibaseurl$macdbrest\n";
 my $matrix = matrix_init($mactable, $infraid);
 
+if ($map_vlans) {
+	$vlan_mappings = reload_vlan_mappings($dbh,$map_vlan_query);
+	$debug && print Dumper ($vlan_mappings);
+}
+
 my $execute_periodic = 0;
 my $quit_after_periodic = 0;
 my $mactablereloadfails = 0;
 
+my $thread;
+
 # handle signals gracefully
 $SIG{TERM} = sub { $execute_periodic = 1; $quit_after_periodic = 1; };
 $SIG{QUIT} = sub { $execute_periodic = 1; $quit_after_periodic = 1; };
@@ -132,7 +145,7 @@ my $sflowpid = open (SFLOWTOOL, '-|', $sflowtool, split(' ', $sflowtool_opts));
 # methodology is to throw away as much crap as possible before parsing
 while (<SFLOWTOOL>) {
 	next unless (substr($_, 0, 4) eq 'FLOW');	# don't use regexp here for performance reasons
-	my ($ipprotocol);
+	my ($ipprotocol,$pvlan);
 
 	chomp;
 
@@ -152,6 +165,14 @@ while (<SFLOWTOOL>) {
 		next;
 	}
 
+	$pvlan = $vlan;
+
+	# if enabled, correct VLAN if there are VLAN translations e.g. for resold customers:
+	if ($vlan_mappings->{$vlan}->{'vlan'}) {
+		print STDERR "DEBUG: [VLAN mapping: VLAN $vlan -> $vlan_mappings->{$vlan}->{'vlan'}]\n" if ($insanedebug);
+		$vlan = $vlan_mappings->{$vlan}->{'vlan'};
+	}
+
 	my $srcvli = getvlifrommactable ($mactable, $infraid, $vlan, $srcmac);
 	my $dstvli = getvlifrommactable ($mactable, $infraid, $vlan, $dstmac);
 
@@ -164,7 +185,7 @@ while (<SFLOWTOOL>) {
 	if ($ipprotocol && $srcvli && $dstvli && ($srcvli != $dstvli) ) {
 		$insanedebug && print STDERR "DEBUG: accepted update for: ".
 			"protocol: $ipprotocol ".
-			"vlan: $vlan ".
+			"vlan: $vlan (pvlan: $pvlan) ".
 			"srcvli: $srcvli ".
 			"dstvli: $dstvli ".
 			"pktsize: $pktsize ".
@@ -179,7 +200,7 @@ while (<SFLOWTOOL>) {
 	} else {
 		$debug && print STDERR "DEBUG: dropped update for: ".
 			"protocol: $ipprotocol ".
-			"vlan: $vlan ".
+			"vlan: $vlan (pvlan: $pvlan) ".
 			"srcvli: $srcvli ".
 			"dstvli: $dstvli ".
 			"pktsize: $pktsize ".
@@ -196,8 +217,11 @@ while (<SFLOWTOOL>) {
 		my $newtv = [gettimeofday()];
 		my $interval = tv_interval($tv, $newtv);
 		$tv = $newtv;
+		my $flush_start_time = time();
 		$debug && print STDERR "DEBUG: starting rrd flush at time interval: $interval, time: ".time()."\n";
-		process_rrd($interval, $matrix, $rrdcached);
+		$thread = threads->create('process_rrd', $interval, $matrix, $rrdcached);
+		$thread->detach();
+
 		if ($quit_after_periodic) {
 			$debug && print STDERR "DEBUG: orderly quit at ".time()."\n";
 			exit 0;
@@ -217,7 +241,8 @@ while (<SFLOWTOOL>) {
 				die "FATAL: could not reload mactable after $mactabletimeout seconds. Aborting.\n";
 			}
 		}
-		$debug && print STDERR "DEBUG: flush completed at ".time()."\n";
+		my $flush_run_time = time() - $flush_start_time;
+		$debug && print STDERR "DEBUG: flush completed at ".time()." (".$flush_run_time."s)\n";
 	}
 }
 
@@ -229,6 +254,7 @@ kill 9, $sflowpid;
 # oops, we should never exit
 die "Oops, input pipe died. Aborting.\n";
 
+
 #
 # write traffic matrix out to RRD file while calculating totals
 #
@@ -283,7 +309,7 @@ sub process_rrd {
 
 				# write per-vlan aggregates out to rrd
 				$rrdfile = sprintf ("$basedir/ipv$ipprotocol/$rrdtype/aggregate/aggregate.ipv$ipprotocol.$rrdtype.vlan%05d.rrd", $vlan);
-				$debug && print STDERR "DEBUG: aggregate: building update for vlan: $vlan type: $rrdtype protocol: $ipprotocol file: $rrdfile\n";
+				$insanedebug && print STDERR "DEBUG: aggregate: building update for vlan: $vlan type: $rrdtype protocol: $ipprotocol file: $rrdfile\n";
 
 				my $in =  $matrix->{aggregate}->{$ipprotocol}->{$rrdtype}->{$vlan}->{in};
 				my $out = $matrix->{aggregate}->{$ipprotocol}->{$rrdtype}->{$vlan}->{out};
@@ -440,3 +466,25 @@ sub reload_mactable
 
 	return $json;
 }
+
+#
+# VLAN translation mappings
+#
+sub reload_vlan_mappings {
+
+    my ($d,$sql) = @_;
+
+	return undef unless ($sql);
+
+	my ($s, $mapping);
+
+	$debug && print STDERR "DEBUG: sql $sql\n";
+
+	$s = $d->prepare("$sql");
+	$s->execute();
+
+	$mapping = $s->fetchall_hashref('pvlan');
+
+	return $mapping;
+
+}