Please, specify your topology (devices/switches/hubs/routers/etc, which one is lwIP) and tell us what you mean by unpluging another side.
Keep Alives are sent between hosts, so L2/L3 devices are usually transparen to them. Regards, Krzysztof Wesołowski, On Tue, Aug 21, 2012 at 11:06 PM, vincent cui <vincent....@enlogic.com> wrote: > You mean that I have to send keep-alive packet to switch and hub to get > response ? if no response, it should be break up ? > > -----Original Message----- > From: lwip-users-bounces+vincent.cui=enlogic....@nongnu.org > [mailto:lwip-users-bounces+vincent.cui=enlogic....@nongnu.org] On Behalf Of > Krzysztof Weso?owski > Sent: 2012年8月22日 4:44 > To: Mailing list for lwIP users > Subject: Re: [lwip-users] how to detect cable down in this case > > On Tue, Aug 21, 2012 at 10:38 PM, Bill Auerbach > <bauerb...@arrayonline.com> wrote: >> I think he means if you are connected to a switch and the connection to >> another device on the switch is removed. In this case there is no loss of >> link since the switch maintains that but there is a loss of connection. > > Now I see, i have to often used config when other end was other end of > physical cable ;) > > There where sevaral topics about detecting connection break, with > techniques like Keep-Alive Packets mentioned. > > TCP/IP itself is capable of delivering packets in connection even when > physical link was down between them, sothere is no simple/ultimate > "other plug out" on this layer. > > Regards, > Krzysztof Wesołowski > > _______________________________________________ > lwip-users mailing list > lwip-users@nongnu.org > https://lists.nongnu.org/mailman/listinfo/lwip-users > _______________________________________________ > lwip-users mailing list > lwip-users@nongnu.org > https://lists.nongnu.org/mailman/listinfo/lwip-users _______________________________________________ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users