yum install bind bind-utils
cat /etc/named.conf
# forwarding reverse lookup
zone "==============>internal reverse lookup IP range<================55.100.in-addr.arpa" in {
type forward;
forwarders { ==================================>internal DNS IPs<====================================; };
};
zone "==================================>internal domain<====================================" in {
type forward;
forwarders { ==================================>internal DNS IPs<====================================; };
};
options {
directory "/var/named";
# Hide version string for security
version "not currently available";
# Listen to the loopback device only
listen-on { any; };
listen-on-v6 { ::1; };
# Do not query from the specified source port range
# (Adjust depending your firewall configuration)
avoid-v4-udp-ports { range 1 32767; };
avoid-v6-udp-ports { range 1 32767; };
# Forward all DNS queries to the public DNS.
forwarders { ==================================>public DNS IP<====================================; };
forward only;
# Expire negative answer ASAP.
# i.e. Do not cache DNS query failure.
max-ncache-ttl 1200; # 3 seconds
# Disable non-relevant operations
allow-transfer { none; };
allow-update-forwarding { none; };
allow-notify { none; };
allow-recursion { any; };
};
service named start
To setup the client config you can then change the nameserver and point to your new forwarding DNS.
PS: do not forget that your nameserver also should be able to resolve through the named and you should set your /etc/resolv.conf nameserver 127.0.0.1.