Ensure we're not using any invalid ssh_minion_opts. We want to make sure
    that the ssh_minion_opts does not override any pillar or fileserver options
    inherited from the master config. To add other items, modify the if
    statement in the for loop below.

def _validate_ssh_minion_opts(opts):
    '''
    Ensure we're not using any invalid ssh_minion_opts. We want to make sure
    that the ssh_minion_opts does not override any pillar or fileserver options
    inherited from the master config. To add other items, modify the if
    statement in the for loop below.
    '''
    ssh_minion_opts = opts.get('ssh_minion_opts', {})
    if not isinstance(ssh_minion_opts, dict):
        log.error('Invalidly-formatted ssh_minion_opts')
        opts.pop('ssh_minion_opts')

    for opt_name in list(ssh_minion_opts):
        if re.match('^[a-z0-9]+fs_', opt_name, flags=re.IGNORECASE) \
                or ('pillar' in opt_name and not 'ssh_merge_pillar' == opt_name) \
                or opt_name in ('fileserver_backend',):
            log.warning(
                '\'%s\' is not a valid ssh_minion_opts parameter, ignoring',
                opt_name
            )
            ssh_minion_opts.pop(opt_name)