Update RHEL cap for setting hostname

plugins/guests/redhat/cap/change_host_name.rb

@@ -1,9 +1,12 @@
+require 'vagrant/util/guest_hosts'
+
 module VagrantPlugins
   module GuestRedHat
     module Cap
       class ChangeHostName
 
         extend Vagrant::Util::GuestInspection::Linux
+        extend Vagrant::Util::GuestHosts::Linux
 
         def self.change_host_name(machine, name)
           comm = machine.communicate
@@ -15,11 +18,6 @@ module VagrantPlugins
               sed -i 's/\\(HOSTNAME=\\).*/\\1#{name}/' /etc/sysconfig/network
               # Update DNS
               sed -i 's/\\(DHCP_HOSTNAME=\\).*/\\1\"#{basename}\"/' /etc/sysconfig/network-scripts/ifcfg-*
-              # Set the hostname - use hostnamectl if available
-              echo '#{name}' > /etc/hostname
-              grep -w '#{name}' /etc/hosts || {
-                sed -i'' '1i 127.0.0.1\\t#{name}\\t#{basename}' /etc/hosts
-              }
             EOH
 
             if hostnamectl?(comm)
@@ -40,6 +38,13 @@ module VagrantPlugins
             end
             comm.sudo(restart_command)
           end
+          
+          network_with_hostname = machine.config.vm.networks.map {|_, c| c if c[:hostname] }.compact[0]
+          if network_with_hostname
+            replace_host(comm, name, network_with_hostname[:ip])
+          else
+            add_hostname_to_loopback_interface(comm, name)
+          end
         end
       end
     end

test/unit/plugins/guests/redhat/cap/change_host_name_test.rb

@@ -26,6 +26,9 @@ describe "VagrantPlugins::GuestRedHat::Cap::ChangeHostName" do
     let(:hostnamectl) { true }
     let(:networkd) { true }
     let(:network_manager) { false }
+    let(:networks) { [
+      [:forwarded_port, {:guest=>22, :host=>2222, :host_ip=>"127.0.0.1", :id=>"ssh", :auto_correct=>true, :protocol=>"tcp"}]
+    ] }
 
     before do
       comm.stub_command("hostname -f | grep '^#{name}$'", exit_code: hostname_changed ? 1 : 0)
@@ -33,12 +36,47 @@ describe "VagrantPlugins::GuestRedHat::Cap::ChangeHostName" do
       allow(cap).to receive(:hostnamectl?).and_return(hostnamectl)
       allow(cap).to receive(:systemd_networkd?).and_return(networkd)
       allow(cap).to receive(:systemd_controlled?).with(anything, /NetworkManager/).and_return(network_manager)
+      allow(machine).to receive_message_chain(:config, :vm, :networks).and_return(networks)
     end
 
-    it "sets the hostname" do
-      cap.change_host_name(machine, name)
-      expect(comm.received_commands[1]).to match(/\/etc\/sysconfig\/network/)
-      expect(comm.received_commands[1]).to match(/\/etc\/sysconfig\/network-scripts\/ifcfg/)
+    context "minimal network config" do 
+      it "sets the hostname" do
+        comm.stub_command("hostname -f | grep '^#{name}$'", exit_code: 1)
+        cap.change_host_name(machine, name)
+        expect(comm.received_commands[1]).to match(/\/etc\/sysconfig\/network/)
+      end
+
+      it "does not change the hostname if already set" do
+        comm.stub_command("hostname -f | grep '^#{name}$'", exit_code: 0)
+        cap.change_host_name(machine, name)
+        expect(comm).to_not receive(:sudo).with(/\/etc\/sysconfig\/network/)
+      end
+    end
+
+    context "multiple networks configured with hostname" do 
+      it "adds a new entry only for the hostname" do 
+        networks = [
+          [:forwarded_port, {:guest=>22, :host=>2222, :host_ip=>"127.0.0.1", :id=>"ssh", :auto_correct=>true, :protocol=>"tcp"}],
+          [:public_network, {:ip=>"192.168.0.1", :hostname=>true, :protocol=>"tcp", :id=>"93a4ad88-0774-4127-a161-ceb715ff372f"}],
+          [:public_network, {:ip=>"192.168.0.2", :protocol=>"tcp", :id=>"5aebe848-7d85-4425-8911-c2003d924120"}]
+        ]
+        allow(machine).to receive_message_chain(:config, :vm, :networks).and_return(networks)
+        expect(cap).to receive(:replace_host)
+        expect(cap).to_not receive(:add_hostname_to_loopback_interface)
+        cap.change_host_name(machine, name)
+      end
+
+      it "appends an entry to the loopback interface" do 
+        networks = [
+          [:forwarded_port, {:guest=>22, :host=>2222, :host_ip=>"127.0.0.1", :id=>"ssh", :auto_correct=>true, :protocol=>"tcp"}],
+          [:public_network, {:ip=>"192.168.0.1", :protocol=>"tcp", :id=>"93a4ad88-0774-4127-a161-ceb715ff372f"}],
+          [:public_network, {:ip=>"192.168.0.2", :protocol=>"tcp", :id=>"5aebe848-7d85-4425-8911-c2003d924120"}]
+        ]
+        allow(machine).to receive_message_chain(:config, :vm, :networks).and_return(networks)
+        expect(cap).to_not receive(:replace_host)
+        expect(cap).to receive(:add_hostname_to_loopback_interface).once
+        cap.change_host_name(machine, name)
+      end
     end
 
     context "when hostnamectl is in use" do
@@ -64,7 +102,7 @@ describe "VagrantPlugins::GuestRedHat::Cap::ChangeHostName" do
 
       it "does not change the hostname" do
         cap.change_host_name(machine, name)
-        expect(comm.received_commands.size).to eq(1)
+        expect(comm.received_commands.size).to eq(2)
       end
     end