环境 AIX 5200-04
问题 在使用telnet登录的用户登出后，last，who等命令仍然会显示该用户在连接中：
#last
root pts/5 node1 Oct 26 09:19 still logged in.
root pts/3 node2 Oct 26 08:54 still logged in.
root pts/2 node3 Oct 26 08:52 still logged in.
root pts/1 node4 Oct 26 08:37 still logged in.
#who
root pts/1 Oct 26 08:37 (node4)
root pts/2 Oct 26 08:52 (node3)
root pts/3 Oct 26 08:54 (node2)
root pts/5 Oct 26 09:19 (node1)
