diff --git a/Netdisco/bin/netdisco-do b/Netdisco/bin/netdisco-do
index db511ddc..6d80f0eb 100755
--- a/Netdisco/bin/netdisco-do
+++ b/Netdisco/bin/netdisco-do
@@ -103,7 +103,6 @@ unless ($action) {
   use App::Netdisco::Util::SNMP ();
   use App::Netdisco::Util::Device
     qw/get_device delete_device renumber_device/;
-  use App::Netdisco::Util::DNS 'hostname_from_ip';
 
   with 'App::Netdisco::Daemon::Worker::Poller::Device';
   with 'App::Netdisco::Daemon::Worker::Poller::Arpnip';
@@ -171,8 +170,6 @@ unless ($action) {
     }
 
     renumber_device($device, $new_dev->ip);
-    my $hostname = hostname_from_ip($device->ip);
-    $device->update({dns => $hostname});
     return ('done', sprintf 'Renumbered device %s to %s (%s).',
       $device->ip, $new_dev->ip, ($hostname || ''));
   }
diff --git a/Netdisco/lib/App/Netdisco/Core/Discover.pm b/Netdisco/lib/App/Netdisco/Core/Discover.pm
index a0e448de..11c674da 100644
--- a/Netdisco/lib/App/Netdisco/Core/Discover.pm
+++ b/Netdisco/lib/App/Netdisco/Core/Discover.pm
@@ -50,21 +50,29 @@ the IP and hostname in the device object for the canonical IP.
 sub set_canonical_ip {
   my ($device, $snmp) = @_;
 
-  my $new_ip  = undef;
   my $old_ip  = $device->ip;
+  my $new_ip  = $old_ip;
   my $ospf_ip = $snmp->root_ip;
   my $revname = ipv4_from_hostname($snmp->name);
 
-  if (setting('device_identity')) {
-  }
-  elsif ((not $new_ip) and setting('reverse_sysname') and $revname) {
-      $new_ip = $revname;
-  }
-  elsif ((not $new_ip) and $ospf_ip) {
+  if ($ospf_ip) {
       $new_ip = $ospf_ip;
   }
 
-  return unless $new_ip and ($new_ip ne $old_ip);
+  if (setting('reverse_sysname') and $revname) {
+      $new_ip = $revname;
+  }
+
+  # check if user has renumbered to an alias
+  if ($new_ip ne $old_ip
+      and $device->device_ips->count({alias => $old_ip})) {
+      $new_ip = $old_ip;
+  }
+
+  if (setting('device_identity')) {
+  }
+
+  return if $new_ip eq $old_ip;
 
   if (not $snmp->snmp_connect_ip( $new_ip )) {
       # should be warning or error?
@@ -101,8 +109,6 @@ sub store_device {
   my $interfaces = $snmp->interfaces;
   my $ip_netmask = $snmp->ip_netmask;
 
-  my $hostname = hostname_from_ip($device->ip);
-  $device->dns($hostname) if $hostname;
   my $localnet = NetAddr::IP::Lite->new('127.0.0.0/8');
 
   # build device aliases suitable for DBIC
@@ -143,7 +149,7 @@ sub store_device {
   my $vtpdomains = $snmp->vtp_d_name;
   my $vtpdomain;
   if (defined $vtpdomains and scalar values %$vtpdomains) {
-      $device->vtp_domain( (values %$vtpdomains)[-1] );
+      $device->set_column( vtp_domain => (values %$vtpdomains)[-1] );
   }
 
   my @properties = qw/
@@ -156,14 +162,14 @@ sub store_device {
   /;
 
   foreach my $property (@properties) {
-      $device->$property( $snmp->$property );
+      $device->set_column( $property => $snmp->$property );
   }
 
-  $device->model(  Encode::decode('UTF-8', $snmp->model)  );
-  $device->serial( Encode::decode('UTF-8', $snmp->serial) );
+  $device->set_column( model  => Encode::decode('UTF-8', $snmp->model)  );
+  $device->set_column( serial => Encode::decode('UTF-8', $snmp->serial) );
 
-  $device->snmp_class( $snmp->class );
-  $device->last_discover(\'now()');
+  $device->set_column( snmp_class => $snmp->class );
+  $device->set_column( last_discover => \'now()' );
 
   schema('netdisco')->txn_do(sub {
     my $gone = $device->device_ips->delete;
diff --git a/Netdisco/lib/App/Netdisco/Util/Device.pm b/Netdisco/lib/App/Netdisco/Util/Device.pm
index ba5d94c4..99038c4d 100644
--- a/Netdisco/lib/App/Netdisco/Util/Device.pm
+++ b/Netdisco/lib/App/Netdisco/Util/Device.pm
@@ -3,6 +3,7 @@ package App::Netdisco::Util::Device;
 use Dancer qw/:syntax :script/;
 use Dancer::Plugin::DBIC 'schema';
 use App::Netdisco::Util::Permission 'check_acl';
+use App::Netdisco::Util::DNS 'hostname_from_ip';
 
 use base 'Exporter';
 our @EXPORT = ();
@@ -115,13 +116,17 @@ sub renumber_device {
 
   my $happy = 0;
   schema('netdisco')->txn_do(sub {
+    $device->renumber($new_ip) or return;
+
     schema('netdisco')->resultset('UserLog')->create({
       username => session('logged_in_user'),
       userip => scalar eval {request->remote_address},
       event => "Renumbered device from $ip to $new_ip",
     });
 
-    $device->renumber($new_ip);
+    my $hostname = hostname_from_ip($device->ip);
+    $device->update({dns => $hostname});
+
     $happy = 1;
   });