def METHOD_NAME( cls ):
    "Check dependencies and warn about firewalling"
    pathCheck( 'brctl', moduleName='bridge-utils' )
    # Disable Linux bridge firewalling so that traffic can flow!
    for table in 'arp', 'ip', 'ip6':
        cmd = 'sysctl net.bridge.bridge-nf-call-%stables' % table
        out = quietRun( cmd ).strip()
        if out.endswith( '1' ):
            warn( 'Warning: Linux bridge may not work with', out, '\n' )