diff --git a/lib/App/Netdisco/Worker/Plugin/Discover/Neighbors.pm b/lib/App/Netdisco/Worker/Plugin/Discover/Neighbors.pm
index 570b951b..16ccb9a7 100644
--- a/lib/App/Netdisco/Worker/Plugin/Discover/Neighbors.pm
+++ b/lib/App/Netdisco/Worker/Plugin/Discover/Neighbors.pm
@@ -127,6 +127,10 @@ sub store_neighbors {
   my $c_id       = $snmp->c_id;
   my $c_platform = $snmp->c_platform;
 
+  # cache the device ports to save hitting the database for many single rows
+  my $device_ports = vars->{'device_ports'}
+    || { map {($_->port => $_)} $device->ports->all };
+
   # v4 and v6 neighbor tables
   my $c_ip = ($snmp->c_ip || {});
   my %c_ipv6 = %{ ($snmp->can('hasLLDP') and $snmp->hasLLDP)
@@ -144,9 +148,9 @@ sub store_neighbors {
           next;
       }
 
-      my $port = $interfaces->{ $c_if->{$entry} };
-      my $portrow = schema('netdisco')->resultset('DevicePort')
-          ->single({ip => $device->ip, port => $port});
+      # WRT #475 this is SAFE because we check against known ports below
+      my $port = $interfaces->{ $c_if->{$entry} } or next;
+      my $portrow = $device_ports->{$port};
 
       if (!defined $portrow) {
           info sprintf ' [%s] neigh - local port %s not in database!',
diff --git a/lib/App/Netdisco/Worker/Plugin/Discover/PortPower.pm b/lib/App/Netdisco/Worker/Plugin/Discover/PortPower.pm
index c355224e..8fc2e34b 100644
--- a/lib/App/Netdisco/Worker/Plugin/Discover/PortPower.pm
+++ b/lib/App/Netdisco/Worker/Plugin/Discover/PortPower.pm
@@ -32,6 +32,10 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
       };
   }
 
+  # cache the device ports to save hitting the database for many single rows
+  my $device_ports = vars->{'device_ports'}
+    || { map {($_->port => $_)} $device->ports->all };
+
   my $interfaces = $snmp->interfaces;
   my $p_ifindex  = $snmp->peth_port_ifindex;
   my $p_admin    = $snmp->peth_port_admin;
@@ -42,11 +46,16 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
   # build device port power info suitable for DBIC
   my @portpower;
   foreach my $entry (keys %$p_ifindex) {
-      my $port = $interfaces->{ $p_ifindex->{$entry} };
-      next unless $port;
+      # WRT #475 this is SAFE because we check against known ports below
+      my $port = $interfaces->{ $p_ifindex->{$entry} } or next;
+
+      if (!defined $device_ports->{$port}) {
+          info sprintf ' [%s] power - local port %s not in database!',
+            $device->ip, $port;
+          next;
+      }
 
       my ($module) = split m/\./, $entry;
-
       push @portpower, {
           port   => $port,
           module => $module,
diff --git a/lib/App/Netdisco/Worker/Plugin/Discover/PortProperties.pm b/lib/App/Netdisco/Worker/Plugin/Discover/PortProperties.pm
index 1680feac..8693e657 100644
--- a/lib/App/Netdisco/Worker/Plugin/Discover/PortProperties.pm
+++ b/lib/App/Netdisco/Worker/Plugin/Discover/PortProperties.pm
@@ -21,10 +21,20 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
   my $interfaces = $snmp->interfaces || {};
   my %properties = ();
 
+  # cache the device ports to save hitting the database for many single rows
+  my $device_ports = vars->{'device_ports'}
+    || { map {($_->port => $_)} $device->ports->all };
+
   my $raw_speed = $snmp->i_speed_raw || {};
 
   foreach my $idx (keys %$raw_speed) {
     my $port = $interfaces->{$idx} or next;
+    if (!defined $device_ports->{$port}) {
+        info sprintf ' [%s] properties/speed - local port %s not in database!',
+          $device->ip, $port;
+        next;
+    }
+
     $properties{ $port }->{raw_speed} = $raw_speed->{$idx};
   }
 
@@ -32,6 +42,12 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
 
   foreach my $idx (keys %$err_cause) {
     my $port = $interfaces->{$idx} or next;
+    if (!defined $device_ports->{$port}) {
+        info sprintf ' [%s] properties/errdis - local port %s not in database!',
+          $device->ip, $port;
+        next;
+    }
+
     $properties{ $port }->{error_disable_cause} = $err_cause->{$idx};
   }
 
@@ -39,6 +55,12 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
 
   foreach my $idx (keys %$faststart) {
     my $port = $interfaces->{$idx} or next;
+    if (!defined $device_ports->{$port}) {
+        info sprintf ' [%s] properties/faststart - local port %s not in database!',
+          $device->ip, $port;
+        next;
+    }
+
     $properties{ $port }->{faststart} = $faststart->{$idx};
   }
 
@@ -54,6 +76,11 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
 
   foreach my $idx (keys %$c_if) {
     my $port = $interfaces->{ $c_if->{$idx} } or next;
+    if (!defined $device_ports->{$port}) {
+        info sprintf ' [%s] properties/lldpcap - local port %s not in database!',
+          $device->ip, $port;
+        next;
+    }
 
     my $remote_cap  = $c_cap->{$idx} || [];
     my $remote_type = Encode::decode('UTF-8', $c_platform->{$idx} || '');
diff --git a/lib/App/Netdisco/Worker/Plugin/Discover/Properties.pm b/lib/App/Netdisco/Worker/Plugin/Discover/Properties.pm
index f2537ca7..f10808fb 100644
--- a/lib/App/Netdisco/Worker/Plugin/Discover/Properties.pm
+++ b/lib/App/Netdisco/Worker/Plugin/Discover/Properties.pm
@@ -252,6 +252,10 @@ register_worker({ phase => 'early', driver => 'snmp' }, sub {
     $device->update_or_insert(undef, {for => 'update'});
     $device->ports->populate([values %interfaces]);
 
+    # cache for later phases of the discovery
+    vars->{'device_ports'} = { map {($_->port => $_)}
+      $device->ports->search(undef, {columns => 'port'})->all };
+
     return Status->info(sprintf ' [%s] interfaces - added %d new interfaces',
       $device->ip, scalar values %interfaces);
   });
diff --git a/lib/App/Netdisco/Worker/Plugin/Discover/VLANs.pm b/lib/App/Netdisco/Worker/Plugin/Discover/VLANs.pm
index 0445661e..f5b1d734 100644
--- a/lib/App/Netdisco/Worker/Plugin/Discover/VLANs.pm
+++ b/lib/App/Netdisco/Worker/Plugin/Discover/VLANs.pm
@@ -33,6 +33,10 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
       };
   }
 
+  # cache the device ports to save hitting the database for many single rows
+  my $device_ports = vars->{'device_ports'}
+    || { map {($_->port => $_)} $device->ports->all };
+
   my $i_vlan            = $snmp->i_vlan;
   my $i_vlan_membership = $snmp->i_vlan_membership;
   my $i_vlan_type       = $snmp->i_vlan_type;
@@ -42,8 +46,13 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
   my @portvlans = ();
   foreach my $entry (keys %$i_vlan_membership) {
       my %port_vseen = ();
-      my $port = $interfaces->{$entry};
-      next unless defined $port;
+      my $port = $interfaces->{$entry} or next;
+
+      if (!defined $device_ports->{$port}) {
+          info sprintf ' [%s] vlans - local port %s not in database!',
+            $device->ip, $port;
+          next;
+      }
 
       my $type = $i_vlan_type->{$entry};
 
diff --git a/lib/App/Netdisco/Worker/Plugin/Discover/Wireless.pm b/lib/App/Netdisco/Worker/Plugin/Discover/Wireless.pm
index a86640af..b80fbc8c 100644
--- a/lib/App/Netdisco/Worker/Plugin/Discover/Wireless.pm
+++ b/lib/App/Netdisco/Worker/Plugin/Discover/Wireless.pm
@@ -18,6 +18,10 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
   my $ssidlist = $snmp->i_ssidlist;
   return unless scalar keys %$ssidlist;
 
+  # cache the device ports to save hitting the database for many single rows
+  my $device_ports = vars->{'device_ports'}
+    || { map {($_->port => $_)} $device->ports->all };
+
   my $interfaces = $snmp->interfaces;
   my $ssidbcast  = $snmp->i_ssidbcast;
   my $ssidmac    = $snmp->i_ssidmac;
@@ -36,6 +40,12 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
           next;
       }
 
+      if (!defined $device_ports->{$port}) {
+          info sprintf ' [%s] wireless - local port %s not in database!',
+            $device->ip, $port;
+          next;
+      }
+
       push @ssids, {
           port      => $port,
           ssid      => $ssidlist->{$entry},
@@ -64,6 +74,12 @@ register_worker({ phase => 'main', driver => 'snmp' }, sub {
           next;
       }
 
+      if (!defined $device_ports->{$port}) {
+          info sprintf ' [%s] wireless - local port %s not in database!',
+            $device->ip, $port;
+          next;
+      }
+
       push @channels, {
           port    => $port,
           channel => $channel->{$entry},
diff --git a/lib/App/Netdisco/Worker/Plugin/Macsuck/Nodes.pm b/lib/App/Netdisco/Worker/Plugin/Macsuck/Nodes.pm
index b46e78a4..ba8da6e9 100644
--- a/lib/App/Netdisco/Worker/Plugin/Macsuck/Nodes.pm
+++ b/lib/App/Netdisco/Worker/Plugin/Macsuck/Nodes.pm
@@ -299,6 +299,8 @@ sub walk_fwtable {
           next;
       }
 
+      # WRT #475 this is SAFE because we check against known ports below
+      # but we do need the SNMP interface IDs to get the job done
       my $port = $interfaces->{$iid};
 
       unless (defined $port) {
@@ -318,6 +320,7 @@ sub walk_fwtable {
       # this uses the cached $ports resultset to limit hits on the db
       my $device_port = $device_ports->{$port};
 
+      # WRT #475 ... see? :-)
       unless (defined $device_port) {
           debug sprintf
             ' [%s] macsuck %s - port %s is not in database - skipping.',