Mastering DNS with BIND: Step‑by‑Step Server Setup and Configuration

What Is DNS?

DNS (Domain Name System) is a client‑server mechanism that translates human‑readable host names into IP addresses. It is a core Internet service and is widely used in enterprise networks.

Roles of DNS Servers

Forward lookup : Resolve a domain name to its IP address.

Reverse lookup : Resolve an IP address to its domain name.

Distributed Data Structure

DNS uses a hierarchical, distributed database. (Diagram omitted for brevity.)

Query Methods

递归查询：大多数客户机向DNS服务器解析域名的方式
迭代查询：大多数DNS服务器向其他DNS服务器解析域名的方式

Types of DNS Servers

Cache server : Caches query results to speed up repeated lookups.

Primary (master) server : Authoritative for a zone, holds the definitive records.

Secondary (slave) server : Retrieves zone data from the primary server.

BIND Overview

BIND (Berkeley Internet Name Daemon) is a widely used DNS server implementation.

BIND official site: https://www.isc.org/
Main daemon: /usr/sbin/named
Service script: /etc/init.d/named
Listening port: 53
Main config file: /etc/named.conf
Zone data directory: /var/named/chroot/var/named/

Key Configuration Files

/etc/named.conf

options {
    listen-on port 53 { 127.0.0.1; };
    listen-on-v6 port 53 { ::1; };
    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 { localhost; };
    recursion yes;
    dnssec-enable yes;
    dnssec-validation yes;
    dnssec-lookaside auto;
    bindkeys-file "/etc/named.iscdlv.key";
};
logging {
    channel default_debug {
        file "data/named.run";
        severity dynamic;
    };
};
zone "." IN {
    type hint;
    file "named.ca";
};
include "/etc/named.rfc1912.zones";

/etc/named.rfc1912.zones

zone "localhost.localdomain" IN {
    type master;
    file "named.localhost";
    allow-update { none; };
};
zone "localhost" IN {
    type master;
    file "named.localhost";
    allow-update { none; };
};
zone ".0.ip4.arpa" IN {
    type master;
    file "named.loopback";
    allow-update { none; };
};
zone "1.0.0.127.in-addr.arpa" IN {
    type master;
    file "named.loopback";
    allow-update { none; };
};
zone "0.in-addr.arpa" IN {
    type master;
    file "named.empty";
    allow-update { none; };
};

/var/named/named.localhost

$TTL 1D
@ IN SOA @ rname.invalid. (
    0 ; serial
    1D ; refresh
    1H ; retry
    1W ; expire
    3H ) ; minimum
    NS @
    A 127.0.0.1
    AAAA ::1

Installing and Starting BIND on Linux

yum install bind

systemctl start named.service

systemctl enable named.service

Configuring the Main File

vim /etc/named.conf
# Change or add:
listen-on-v6 port 53 { any; };
allow-query { any; };

Creating Zone Files

Forward zone for example.com

zone "example.com." IN {
    type master;
    file "example.com.zone";
    allow-update { none; };
};

Reverse zone for 192.168.134.0/24

zone "134.168.192.in-addr.arpa" IN {
    type master;
    file "134.168.192.zone";
    allow-update { none; };
};

Preparing Zone Files

cp /var/named/named.empty /var/named/example.com.zone
cp /var/named/named.empty /var/named/134.168.192.zone
chown :named example.com.zone

Sample Forward Zone (example.com)

$TTL 3H
@ IN SOA example.com. root.example.com. (
    0 ; serial
    1D ; refresh
    1H ; retry
    1W ; expire
    3H ) ; minimum
    NS dns.example.com.
    A 192.168.134.139
    www A 192.168.134.139

Sample Reverse Zone (134.168.192.in-addr.arpa)

$TTL 3H
@ IN SOA example.com. root.example.com. (
    0 ; serial
    1D ; refresh
    1H ; retry
    1W ; expire
    3H ) ; minimum
    NS dns.example.com.
    139 PTR example.com.

Network Interface Configuration

vim /etc/sysconfig/network-scripts/ifcfg-ens33
BOOTPROTO=static
IPADDR1=192.168.134.139
NETMASK=255.255.255.0
GATEWAY=192.168.134.2
DNS1=192.168.134.139

Starting and Verifying the DNS Service

systemctl start named.service
named-checkconf

Client Configuration

vim /etc/resolv.conf
nameserver 192.168.134.139

Testing the DNS Server

On a client machine, use nslookup or dig to query the configured domains and verify forward and reverse resolution.