TCP wrappers /etc/hosts.allow /etc/hosts.deny

A simple example on linux box:

[root@test ~]# cat /etc/hosts.allow
sshd : ALL EXCEPT host1.example.com
snmpd : ALL EXCEPT host1.example.com
ALL : localhost

[root@test ~]# cat /etc/hosts.deny
ALL:ALL

And here's explaining:

Service "sshd/snmpd" will accept connections from all hosts except host1.example.com. All services will accept connections from localhost. Other services will deny connections from all hosts.

 

Good Luck & Best Wishes