Can I Limit the IP(s) that sshd Listens On?

To limit the IP addresses which sshd listens on, you just need to modify its settings within the sshd_configfile. Follow these 4 easy steps:

1. First, backup the sshd_config file, then edit it with your favorite editor.
2. Now, to limit the IPs sshd listens on, you need to change the ListenAddress configuration line:root@root [~]# cd /etc/ssh/
   root@root [/etc/ssh]# cp sshd_config sshd_config.save
   root@root [/etc/ssh]# vi sshd_config
   root@root [/etc/ssh]# diff sshd_config sshd_config.save
   15c15
   < ListenAddress 10.0.0.1
   —
   > #ListenAddress 0.0.0.0
3. Next, restart sshd and verify that it’s listening on the specified address:root@root [/etc/ssh]# /etc/init.d/sshd restart
   Stopping sshd: [ OK ]
   Starting sshd: [ OK ]
   root@root [/etc/ssh]# netstat -anp | grep sshd
   tcp 0 0 10.0.0.1:22 0.0.0.0:* LISTEN 1718/sshd
4. If you want sshd to listen on more than one address, then add additional ListenAddress lines to the configuration file:root@root [/etc/ssh]# diff sshd_config sshd_config.save
   15,16c15
   < ListenAddress 10.0.0.1
   < ListenAddress 10.0.0.2
   —
   > #ListenAddress 0.0.0.0

   root@root [/etc/ssh]# /etc/init.d/sshd restart
   Stopping sshd: [ OK ]
   Starting sshd: [ OK ]
   root@root [/etc/ssh]# netstat -anp | grep sshd
   tcp 0 0 10.0.0.1:22 0.0.0.0:* LISTEN 1884/sshd
   tcp 0 0 10.0.0.2:22 0.0.0.0:* LISTEN 1884/sshd

And there you have it!