Thank you sir I did set 1472 as mtu on rtr. Set it back to 1500. Bang. Back in business.
Sent from my iPhone > On Jan 7, 2020, at 9:51 PM, Ryan Rawdon <[email protected]> wrote: > > >> On Jan 7, 2020, at 3:30 PM, Bejiita78 . <[email protected]> wrote: >> >> has anyone ever noticed that locally a system may respond just fine, but >> running a command like port make install or top would cause the ssh session >> to hang indefinitely? > > This is a common sign of a MTU mismatch on a network segment somewhere > between your client and the server (large segments/packets/frames go into a > black hole and nobody knows); or the path has a properly-configured reduced > MTU, but the server is sending the traffic with the Don’t Fragment bit set > (IP header); but the device in the path dropping it due to a smaller MTU is > not successfully having Packet Too Big ICMP errors get back to the server. > > If you perform a packet capture on the server, you will likely see it > retransmitting one or more segments over and over - but not see those > arriving to the client. > > The approach to diagnosing the point of the issue being introduced (MTU > mismatch, ICMP filtering, or the server not utilizing ICMP PTB responses > properly) depends largely on the network topology between your client and > server; and your ability to investigate or reproduce the symptoms in systems > along that path. > > There are plenty of other potential causes for this behavior, but this is the > first one I would investigate if experiencing this issue. Have there been > any network changes near your client or server that might have meddled with > MTU sizes or ICMP blocking? > _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "[email protected]"
