Add support for checking host against global known host files.

lib/ansible/runner/connection_plugins/ssh.py

@@ -118,14 +118,22 @@ class Connection(object):
 
     def not_in_host_file(self, host):
         if 'USER' in os.environ:
-            host_file = os.path.expandvars("~${USER}/.ssh/known_hosts")
+            user_host_file = os.path.expandvars("~${USER}/.ssh/known_hosts")
         else:
-            host_file = "~/.ssh/known_hosts"
-        host_file = os.path.expanduser(host_file)
-        if not os.path.exists(host_file):
-            print "previous known host file not found"
-            return True
-        host_fh = open(host_file)
+            user_host_file = "~/.ssh/known_hosts"
+        user_host_file = os.path.expanduser(user_host_file)
+        
+        host_file_list = []
+        host_file_list.append(user_host_file)
+        host_file_list.append("/etc/ssh/ssh_known_hosts")
+        host_file_list.append("/etc/ssh/ssh_known_hosts2")
+        
+        hfiles_not_found = 0
+        for hf in host_file_list:
+            if not os.path.exists(hf):
+                hfiles_not_found += 1
+                continue
+            host_fh = open(hf)
             data = host_fh.read()
             host_fh.close()
             for line in data.split("\n"):
@@ -147,6 +155,9 @@ class Connection(object):
                     # standard host file entry
                     if host in tokens[0]:
                         return False
+
+        if (hfiles_not_found == len(host_file_list)):
+            print "previous known host file not found"
         return True
 
     def exec_command(self, cmd, tmp_path, sudo_user=None, sudoable=False, executable='/bin/sh', in_data=None, su_user=None, su=False):