RHCE Series: DNS

Install bind: yum -y install bind

Setup caching-only name server with forwarders.

[root@server1 etc]# cat named.conf
//
// named.conf
//
// Provided by Red Hat bind package to configure the ISC BIND named(8) DNS
// server as a caching only nameserver (as a localhost DNS resolver only).
//
// See /usr/share/doc/bind*/sample/ for example named configuration files.
//

options {
 listen-on port 53 { any; }; //listen on any network
 listen-on-v6 port 53 { any; }; //listen on any network
 directory  "/var/named";
 dump-file  "/var/named/data/cache_dump.db";
        statistics-file "/var/named/data/named_stats.txt";
        memstatistics-file "/var/named/data/named_mem_stats.txt";
 allow-query     { 192.168.1.0/24; }; //define who to allow queries from
 forwarders { 8.8.8.8; }; //add this line to forward queries
 recursion yes;

 dnssec-enable yes;
 dnssec-validation yes;
 dnssec-lookaside auto;

 /* Path to ISC DLV key */
 bindkeys-file "/etc/named.iscdlv.key";

 managed-keys-directory "/var/named/dynamic";
};

logging {
        channel default_debug {
                file "data/named.run";
                severity dynamic;
        };
};

zone "." IN {
 type hint;
 file "named.ca";
};

include "/etc/named.rfc1912.zones";
include "/etc/named.root.key";

Open up the firewall:

iptables -I INPUT -p udp --dport 53 -j ACCEPT
service iptables save

Start the service and make it persistent at boot:

service named start
chkconfig named on