SSH utils with connection fail-overs

sshutils.py

import paramiko
import sys

SERVERS = ['<my first ssh server ip>', '<my second ssh server ip>', '<my third ssh server ip>']
USER = 'genius'
PASSWORD = 'mygeniuspassword'

class MySSHClient():
	
	def __init__(self, domains=SERVERS, username=USER, password=PASSWORD):

		self.domains = domains
		self.username = username
		self.password = password
		
		self.return_str = ''
		self.has_error = False
	
	def do_connect(self):
		for domain in self.domains:
			print "Trying to connect to %s" % domain
			try:
				self.connection = paramiko.SSHClient()
				self.connection.set_missing_host_key_policy(paramiko.AutoAddPolicy())
				self.connection.connect(domain, username=self.username, password=self.password)
				print "Connected to %s" % domain
				break
			except paramiko.AuthenticationException as e:
				print "Authentication failed when connecting to %s\n" % domain
				print "Error details: %s" % e
				sys.exit(1)
			except:
				print "Could not connect to %s. Try another host." % domain
				if self.domains.index(domain) >= (len(self.domains) -1):
					print "Could not connect to all hosts. Giving up!"
					sys.exit(1)


	def execute_command(self, command):
		if command:
			stdin, stdout, stderr = self.connection.exec_command(command)
			stdin.close()
			
			error = str(stderr.read())
			
			if error:
				self.has_error = True
				self.return_str = error
				print 'has error'
			else:
				# reset has_error to the default value
				self.has_error = False
				self.return_str = str(stdout.read())
				print 'no error'

			print self.return_str
		else:
			print "no command to execute"
		
	def do_close(self):
		self.connection.close()