ssh断线自动登录

ssh出于安全考虑，设置了闲置后自动断开功能，这给长时间进行远程操作及利用ssh穿qiang的同学带来了极大的不便，参考了网上的N种方法，实现如下

#!/usr/bin/expect
# Auto login ssh

set user "username";
set passwd "password";
set host "ip";
set id1 1;

while (1) {
        set isconnected 0;
        spawn /usr/bin/ssh -D7070 $user@$host;
        set id1 $spawn_id
        match_max 100000;
        set timeout 60;
        expect {
                "password:" {
                        send "$passwd\r";
                        expect "jailshell" {
                                set isconnected 1;
                                puts "connected to $host succeed";
                                puts $spawn_id;
                        }
                 }

                "closed" {
                        set isconnected 0;
                        #puts "connected to $host fail"

                }

        }

        if { $isconnected == 0 } {
                close;
                puts "SSH server connect fail,retrying...";
                continue;

        }

        while (1) {
                set isconnected 0;
                interact {
                        timeout 22 {
                                set timeout 10;
                                send "echo im active\r";
                                expect "*im active*" { set isconnected 1 }
                                if { $isconnected == 1 } {
                                        puts "on line\r";
                                        continue;
                                } else {
                                        puts "off line\r"
                                        break;
                                }
                        }
        close;
        puts "SSH server connect fails,retrying...";
}