我有一台 debian 机器，在那里我很难通过 ssh 登录。通过 ssh 在服务器上执行命令没问题——只是我没有得到提示，但连接再次终止：
> ssh root@192.168.2.109
Linux debian 2.6.32-5-kirkwood #1 Sun May 6 16:57:51 UTC 2012 armv5tel
The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.
Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Wed Apr 17 21:54:34 2013 from 192.168.2.101
Connection to 192.168.2.109 closed.
正如我所说，运行命令效果很好：
> ssh root@192.168.2.109 cat /etc/bash.bashrc …