Retry all SSH commands on Net::SSH::Disconnect

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## 0.7.3 (unreleased)
 
+  - Retry all SSH on Net::SSH::Disconnect in case SSH is just restarting. [GH-313]
   - Add NFS shared folder support for Arch linux. [GH-346]
   - Fix issue with unknown terminal type output for sudo commands.
   - Forwarded port protocol can now be set as UDP. [GH-311]

lib/vagrant/ssh/session.rb

@@ -61,7 +61,7 @@ module Vagrant
       # the actual `exec!` implementation, except that this
       # implementation also reports `:exit_status` to the block if given.
       def exec!(command, options=nil, &block)
-        retryable(:tries => 5, :on => IOError, :sleep => 0.5) do
+        retryable(:tries => 5, :on => [IOError, Net::SSH::Disconnect], :sleep => 1.0) do
           metach = session.open_channel do |channel|
             channel.exec(command) do |ch, success|
               raise "could not execute command: #{command.inspect}" unless success