Retry SSH commands 5 times if an IOError occurs

lib/vagrant/ssh.rb

@@ -160,25 +160,32 @@ module Vagrant
           ch[:result] << data if [:stdout, :stderr].include?(type)
         end
 
-        metach = session.open_channel do |channel|
-          channel.exec(command) do |ch, success|
-            raise "could not execute command: #{command.inspect}" unless success
+        tries = 5
 
-            # Output stdout data to the block
-            channel.on_data do |ch2, data|
-              block.call(ch2, :stdout, data)
-            end
+        begin
+          metach = session.open_channel do |channel|
+            channel.exec(command) do |ch, success|
+              raise "could not execute command: #{command.inspect}" unless success
 
-            # Output stderr data to the block
-            channel.on_extended_data do |ch2, type, data|
-              block.call(ch2, :stderr, data)
-            end
+              # Output stdout data to the block
+              channel.on_data do |ch2, data|
+                block.call(ch2, :stdout, data)
+              end
 
-            # Output exit status information to the block
-            channel.on_request("exit-status") do |ch2, data|
-              block.call(ch2, :exit_status, data.read_long)
+              # Output stderr data to the block
+              channel.on_extended_data do |ch2, type, data|
+                block.call(ch2, :stderr, data)
+              end
+
+              # Output exit status information to the block
+              channel.on_request("exit-status") do |ch2, data|
+                block.call(ch2, :exit_status, data.read_long)
+              end
             end
           end
+        rescue IOError
+          retry if (tries -= 1) > 0
+          raise
         end
 
         metach.wait

test/vagrant/actions/vm/forward_ports_test.rb

@@ -139,6 +139,7 @@ class ForwardPortsActionTest < Test::Unit::TestCase
 
       @vm.expects(:forwarded_ports).returns(forwarded_ports)
       @vm.expects(:save).once
+      @runner.expects(:reload!).once
       @action.forward_ports
     end
   end
@@ -151,6 +152,7 @@ class ForwardPortsActionTest < Test::Unit::TestCase
       @vm.expects(:network_adapters).returns([network_adapter])
       network_adapter.expects(:attachment_type).returns(:host_only)
       @vm.expects(:save).once
+      @runner.expects(:reload!).once
       @action.forward_ports
     end
   end

test/vagrant/ssh_session_test.rb

@@ -8,6 +8,15 @@ class SshTest < Test::Unit::TestCase
     @instance = @klass.new(@session)
   end
 
+  context "exec!" do
+    should "retry 5 times" do
+      @session.expects(:open_channel).times(5).raises(IOError)
+      assert_raises(IOError) {
+        @instance.exec!("foo")
+      }
+    end
+  end
+
   context "checking exit status" do
     should "raise an ActionException if its non-zero" do
       assert_raises(Vagrant::Actions::ActionException) {