Linux settings allow and disallow access to IP Host.allow and Host.deny

for network services that can be started by xinetd programs, such as FTP telnet, we can modify the configuration of/etc/hosts.allow and/etc/hosts.deny to license or deny which IP, host, user can access.

For example, we are/etc/hosts.allowJoin in
all:218.24.129.
This will allow you to come from218.24.129.*access to all clients of the domain. This is just an example, in fact, the system by default, are able to use these network services

If we are in/etc/hosts.denyrestrictions on the inclusion of218.24.129.*All of the IP for the domain.
all:218.24.129.

If we are in/etc/hosts.denyJoin in
all:218.24.129.134, which limits all218.24.129.134access to all users in the.

When Hosts.allow and Host.deny conflict, the optimization is set with Hosts.allow.

After setting up, to restart
#/etc/rc.d/init.d/xinetd Restart
#/etc/rc.d/init.d/network Restart

Not all service programs can be used tcp_wrappers , such as the use of commands ldd/usr/sbin/sshd , if the output has LibWrap , you can use tcp_wrappers, which means that the service can use/etc/hosts.allow and/etc/hosts.deny, which is not available if the output is not libwrap

Linux settings allow and disallow access to IP Host.allow and Host.deny