Cycle through all the possible credentials and return the first one that
    works.

def _find_credentials(host):
    '''
    Cycle through all the possible credentials and return the first one that
    works.
    '''
    user_names = [__pillar__['proxy'].get('username', 'root')]
    passwords = __pillar__['proxy']['passwords']
    for user in user_names:
        for password in passwords:
            try:
                # Try to authenticate with the given user/password combination
                ret = salt.modules.vsphere.system_info(host=host,
                                                       username=user,
                                                       password=password)
            except SaltSystemExit:
                # If we can't authenticate, continue on to try the next password.
                continue
            # If we have data returned from above, we've successfully authenticated.
            if ret:
                return user, password
    # We've reached the end of the list without successfully authenticating.
    raise SaltSystemExit('Cannot complete login due to an incorrect user name or password.')