[root@linux /]#echo "export tmout=900" >> /etc/profile
[root@linux /]# source /etc/profile
[root@linux /]# vi /etc/ssh/sshd_config
[root@linux /]#echo "export tmout=900" >> /etc/profile
[root@linux /]# source /etc/profile
[root@linux /]# vi /etc/ssh/sshd_config