飞腾shellinabox连接账号立刻断开连接问题定位解决

总述
shellinbox有一个内建的web server作为基本的web ssh client客户端，允许你通过指定的端口访问linux服务器端的sshd shell，只要你的浏览器支持AJAX/JS/CSS就可以访问，不需要额外的浏览器插件，十分的简单操作，软件轻量级；

问题
飞腾2000的shellinabox-2.14版本连接sshd-7.3版本存在问题，现象是输入root账号，不弹出提示输入密码“root@127.0.0.1’s password: ”信息，并且会立刻断开连接，定位过程记录如下：

调试一：-d调试模式启动sshd

[root@IDS practice]# /usr/local/sbin/sshd -d
debug1: userauth-reuest for user root service ssh-connection method none
debug1: attempt 0 failures 0
Failed none for root from 127.0.0.1 port 41236 ssh2
debug1: userauth-request for user root ervice ssh-connection method keyboard-interactive
debug1: attempt 1 failures 0
debug1: keyboard-interactive des
debug1: auth2_challenge: user=root devs=
debug1: kbdint_alloc: devices ‘’
Failed keyboard-interactive forroot from 127.0.0.1 port 41236 ssh2
Excess permission or bad ownership on file /var/log/btmp
debug1: userauth-equest for user root service ssh-connection method password
debug1: attempt 2 failures 0
Failed password for rot from 127.0.0.1 port 41236 ssh2
Excess permission or bad ownership on file /var/log/btmp
debug1: userauth-reqest for user root service ssh-connection method password
debug1: attempt 3 failures 1
Failed password for rootfrom 127.0.0.1 port 41236 ssh2
Excess permission or bad ownership on file /var/log/btmp
debug1: userauth-request for user root service ssh-connection method password
debug1: attempt 4 failures 2
Failed password for root frm 127.0.0.1 port 41236 ssh2
Excess permission or bad ownership on file /var/log/btmp
Connection closed by 127…0.1