DNS adalah kepanjangan dari Domain Name System. Merupakan sebuah sistem yang digunakan untuk menyimpan informasi tentang host dan domain yang terhubung di jaringan. Digunakan untuk mapping dari alamat IP agar mudah dikenali.
DNS Server merupakan server yang digunakan untuk menerjemahkan IP Address ke hostname, ataupun sebaliknya menerjemahkan hostname ke IP Address.
DNS Server di linux biasanya dijalankan oleh program yang bernama named.
Install BIND / Named di CentOS
yum install bind bind-utils /etc/init.d/named start chkconfig named on
Konfigurasi Named
Setelah terinstall, edit file /etc/named.conf
vi /etc/named.conf
Kemudian konfigurasinya seperti contoh:
//
// 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-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 { any; };
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";
zone "hostingdna.info" IN {
type master;
file "hostingdna.info";
allow-update { none; };
};
Menambah Zone DNS
Sebagai contoh menambah DNS record untuk domain hostingdna.info
vi /var/named/hostingdna.info
Kemudian DNS Zone seperti contoh ini:
; Zone file for hostingdna.info
$TTL 300
hostingdna.info. 300 IN SOA ns1.hostingdna.info. master.hostingdna.info. (
2010032506 ;Serial Number
300 ;refresh
7200 ;retry
3600000 ;expire
300 ;minimum
)
hostingdna.info. 300 IN NS ns1.hostingdna.info.
hostingdna.info. 300 IN NS ns2.hostingdna.info.
hostingdna.info. 300 IN A 69.163.37.170
localhost 300 IN A 127.0.0.1
hostingdna.info. 300 IN MX 0 mail.hostingdna.info.
mail 300 IN CNAME hostingdna.info.
www 300 IN CNAME hostingdna.info.
ftp 300 IN A 69.163.37.170
ns1 14400 IN A 69.163.37.170
ns2 14400 IN A 69.163.37.170
Perlu diketahui, jika kita membuat zone record yg lain,
Jika menambah record DNS baru, bind harus direload
service named reload