> Date: Thu, 13 Jan 2005 07:51:16 +0100 > From: Marian Durkovic <[EMAIL PROTECTED]> > > Hi, > > > 08:20:12.680313 aaa.es.net.ssh > bbb.es.net.54854: . 10145:11573(1428) > > ack 31040 win 58548 <nop,nop,timestamp 9068204 69095244> [flowlabel > > 0x6ae53] > > len 1460, hlim 64) > > 1428 bytes is the proper payload length for TCPv6 with options > 1448 bytes is the same for TCPv4 > > 1440 bytes is the payload length for TCPv6 without options > 1460 byts is the same for TCPv4 > > If such packets are failing, your path MTU is probably not 1500 bytes but > smaller.
Indeed, that is the case. One link is via a GRE tunnel and that is restricting MTU. What I don't understand is how this is happening. tcp.mssdflt is set to 1400 bytes and tcp.v6mssdflt is only 1024. If PMTU discovery was working, this should not be a problem. If PMTU discovery is not used, the MSS defaults should keep the packets small enough to work over the tunnel. -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: [EMAIL PROTECTED] Phone: +1 510 486-8634 _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "[EMAIL PROTECTED]"
