--- /tmp/etc/dhcp/dhclient-enter-hooks.d/resolved	2018-04-20 19:55:56.000000000 +0300
+++ /etc/dhcp/dhclient-enter-hooks.d/resolved	2018-05-11 13:39:59.513700826 +0300
@@ -28,29 +28,48 @@
               fi
               statedir="/run/systemd/resolved.conf.d"
               mkdir -p $statedir
+              local updated
+              updated=''
+              local tmpi
+              tmpi=$(mktemp)
               if [ -n "$new_domain_name_servers" ] ; then
-                  cat <<EOF >$statedir/isc-dhcp-v4-$interface.conf
+                  cat <<EOF >$tmpi
 [Resolve]
 DNS=$new_domain_name_servers
 EOF
                   if [ -n "$new_domain_name" ] || [ -n "$new_domain_search" ] ; then
-                      cat <<EOF >>$statedir/isc-dhcp-v4-$interface.conf
+                      cat <<EOF >>$tmpi
 Domains=$new_domain_search $new_domain_name
 EOF
                   fi
+                  local v4ic
+                  v4ic=$statedir/isc-dhcp-v4-$interface.conf
+                  if ! [ -f $v4ic ] || ! cmp $tmpi $v4ic
+                  then cp -a $tmpi $v4ic
+                       chmod +r $v4ic
+                       updated=y
+                  fi
               fi
               if [ -n "$new_dhcp6_name_servers" ] ; then
-                  cat <<EOF >$statedir/isc-dhcp-v6-$interface.conf
+                  cat <<EOF >$tmpi
 [Resolve]
 DNS=$new_dhcp6_name_servers
 EOF
                   if [ -n "$new_dhcp6_domain_search" ] ; then
-                      cat <<EOF >>$statedir/isc-dhcp-v6-$interface.conf
+                      cat <<EOF >>$tmpi
 Domains=$new_dhcp6_domain_search
 EOF
                   fi
+                  local v6ic
+                  v6ic=$statedir/isc-dhcp-v6-$interface.conf
+                  if ! [ -f $v6ic ] || ! cmp $tmpi $v6ic
+                  then cp -a $tmpi $v6ic
+                       chmod +r $v6ic
+                       updated=y
+                  fi
               fi
-              systemctl try-reload-or-restart systemd-resolved.service
+              rm $tmpi
+              [ "$updated" ] && systemctl try-reload-or-restart systemd-resolved.service
           }
                 ;;
 
@@ -58,15 +77,23 @@
               if [ ! "$interface" ] ; then
                   return
               fi
-              rm -f /run/systemd/resolved.conf.d/isc-dhcp-v4-$interface.conf
-              systemctl try-reload-or-restart systemd-resolved.service
+              local v4ic
+              v4ic=/run/systemd/resolved.conf.d/isc-dhcp-v4-$interface.conf
+              if [ -f $v4ic ]
+              then rm -f $v4ic
+                   systemctl try-reload-or-restart systemd-resolved.service
+              fi
               ;;
           EXPIRE6|RELEASE6|STOP6)
               if [ ! "$interface" ] ; then
                   return
               fi
-              rm -f /run/systemd/resolved.conf.d/isc-dhcp-v6-$interface.conf
-              systemctl try-reload-or-restart systemd-resolved.service
+              local v6ic
+              v6ic=/run/systemd/resolved.conf.d/isc-dhcp-v6-$interface.conf
+              if [ -f $v6ic ]
+              then rm -f $v6ic
+                   systemctl try-reload-or-restart systemd-resolved.service
+              fi
               ;;
         esac
 fi