I am running OpenSSH_6.7p1 on Slackware 14.1 x64. I haven't modified a stock config. On Linux TCP timeouts are controlled by these 3 files: $ cat /proc/sys/net/ipv4/tcp_keepalive_time \ > /proc/sys/net/ipv4/tcp_keepalive_intvl \ > /proc/sys/net/ipv4/tcp_keepalive_probes 7200 75 9 These are their default values. I modified them to 3, 1, 1 respecitively before establishing a new SSH connection. After establishing an SSH connection to a machine next to me I unplugged a network cable on the remote machine and had to wait for 3 seconds for the SSH session to be terminated by Linux. This is what I expected. Next, I connected again and while SSH session was already opened I changed values to their defaults - 7200, 75, 9. After unplugging a network cable I wasn't disconnected within 3 seconds. It made me think that it's possible to modify TCP timeouts of opened TCP sockets such as SSH connections. However, after connecting to the same machine again I changed timeout values to 3, 1, 1 again. To my surpires, after unplugging a network cable on the remote side I wasn't disconnected within 3 seconds. It seems it's only possible to increase TCP timeout values when SSH session is already opened but not to lower them. Why? Is it Linux or OpenSSH thing? -- <wempwer@xxxxxxxxx> _______________________________________________ openssh-unix-dev mailing list openssh-unix-dev@xxxxxxxxxxx https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev
