docker.rb in beaker-3.17.0

- old
+ new

@@ -244,13 +244,16 @@
           RUN mkdir -p /var/run/sshd
           RUN echo root:#{root_password} | chpasswd
         EOF
 
         # Configure sshd service to allowroot login using password
+        # Also, disable reverse DNS lookups to prevent every. single. ssh
+        # operation taking 30 seconds while the lookup times out.
         dockerfile += <<-EOF
           RUN sed -ri 's/^#?PermitRootLogin .*/PermitRootLogin yes/' /etc/ssh/sshd_config
           RUN sed -ri 's/^#?PasswordAuthentication .*/PasswordAuthentication yes/' /etc/ssh/sshd_config
+          RUN sed -ri 's/^#?UseDNS .*/UseDNS no/' /etc/ssh/sshd_config
         EOF
 
 
         # Any extra commands specified for the host
         dockerfile += (host['docker_image_commands'] || []).map { |command|
@@ -283,9 +286,12 @@
       container.exec(['sed','-ri',
                       's/^#?PermitRootLogin .*/PermitRootLogin yes/',
                       '/etc/ssh/sshd_config'])
       container.exec(['sed','-ri',
                       's/^#?PasswordAuthentication .*/PasswordAuthentication yes/',
+                      '/etc/ssh/sshd_config'])
+      container.exec(['sed','-ri',
+                      's/^#?UseDNS .*/UseDNS no/',
                       '/etc/ssh/sshd_config'])
       container.exec(%w(service ssh restart))
     end
 
 