Do not do useless work before needed

1 files changed, 5 insertions, 5 deletions

diff --git a/etc/inc/services.inc b/etc/inc/services.inc
index 702ec90..abbc446 100644
--- a/etc/inc/services.inc
+++ b/etc/inc/services.inc
@@ -892,12 +892,12 @@ function services_dhcpdv6_configure() {
 
 	/* we add a fake entry for interfaces that are set to track6 another WAN */
 	foreach ($Iflist as $ifname) {
-		$realif = get_real_interface($ifname);
-		$ifcfgipv6 = get_interface_ipv6($ifname);
-		if(!is_ipaddrv6($ifcfgipv6))
-			continue;
-		$ifcfgipv6 = Net_IPv6::getNetmask($ifcfgipv6, 64);
 		if (!empty($config['interfaces'][$ifname]['track6-interface'])) {
+			$realif = get_real_interface($ifname);
+			$ifcfgipv6 = get_interface_ipv6($ifname);
+			if(!is_ipaddrv6($ifcfgipv6))
+				continue;
+			$ifcfgipv6 = Net_IPv6::getNetmask($ifcfgipv6, 64);
 			$trackifname = $config['interfaces'][$ifname]['track6-interface'];
 			$trackcfg = $config['interfaces'][$trackifname];
 			$pdlen = calculate_ipv6_delegation_length($trackifname);