Localhost Resolver :
(a) install bind
yum install bind bind-chroot bind-devel
(b) Copy named.conf and related files from /usr/share/doc/bind-9.3.6/sample/etc/
cp /usr/share/doc/bind-9.3.6/sample/etc/* /var/named/chroot/etc/
(c) File lists in /var/named/chroot/etc are as bellows :
[root@publicdns1 etc]# ls localtime named.rfc1912.zones rndc.conf named.conf named.root.hints rndc.key
Check the Ownership of files. Ownership should be root:named as
bellow:
[root@publicdns1 etc]# pwd /var/named/chroot/etc [root@publicdns1 etc]# ls -al total 64 drwxr-x--- 2 root named 4096 Aug 28 13:38 . drwxr-x--- 6 root named 4096 Aug 28 13:37 .. -rw-r--r-- 1 root root 3661 Aug 24 12:53 localtime -rw-r--r-- 1 root named 5299 Aug 28 13:38 named.conf -rw-r--r-- 1 root named 775 Aug 28 12:20 named.rfc1912.zones -rw-r--r-- 1 root named 524 Aug 28 12:20 named.root.hints -rw-r--r-- 1 root named 0 Aug 28 12:20 rndc.conf -rw-r----- 1 root named 113 Aug 28 12:12 rndc.key [root@publicdns1 etc]#
If the ownership is not right then we can change it as follows :
chown root:named named.conf named.rfc1912.zones named.root.hints rndc.conf rndc.key
(d) Copy named.root into /var/named/chroot/var/named directory
cp /usr/share/doc/bind-9.3.6/sample/var/named/named.root /var/named/chroot/var/named/
File lists are :
[root@publicdns1 named]# ls data domain.co.uk.zone named.root slaves [root@publicdns1 named]#
(e) For allowing internal pc’s to resolve dns request and for internal host name , we need to work on “view “localhost_resolver” ” section as bellow
view "localhost_resolver"
{
/* This view sets up named to be a localhost resolver ( caching only nameserver ).
* If all you want is a caching-only nameserver, then you need only define this view:
*/
match-clients { localhost;10.0.0.0/24; };
match-destinations { localhost;10.0.0.0/24; };
recursion yes;
# all views must contain the root hints zone:
include "/etc/named.root.hints";
/* these are zones that contain definitions for all the localhost
* names and addresses, as recommended in RFC1912 - these names should
* ONLY be served to localhost clients:
*/
include "/etc/named.rfc1912.zones";
};Note : all the internal zone information will be placed on named.rfc1912.zones files
(f) Now edit named.rfc1912.zones which is located /var/named/chroot/etc
and enter bellow lines
zone “internaldomain.local” IN {
type master;
file “internaldomain.local.zone”;
};
So the Edited named.rfc1912.zones file be like bellow
// named.rfc1912.zones:
//
// Provided by Red Hat caching-nameserver package
//
// ISC BIND named zone configuration for zones recommended by
// RFC 1912 section 4.1 : localhost TLDs and address zones
//
// See /usr/share/doc/bind*/sample/ for example named configuration files.
//
//zone "." IN {
// type hint;
// file "named.ca";
//};
zone "internaldomain.local" IN {
type master;
file "internaldomain.local.zone";
};
zone "localdomain" IN {
type master;
file "localdomain.zone";
allow-update { none; };
};
zone "localhost" IN {
type master;
file "localhost.zone";
allow-update { none; };
};
zone "0.0.127.in-addr.arpa" IN {
type master;
file "named.local";
allow-update { none; };
};
zone "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa" IN {
type master;
file "named.ip6.local";
allow-update { none; };
};
zone "255.in-addr.arpa" IN {
type master;
file "named.broadcast";
allow-update { none; };
};
zone "0.in-addr.arpa" IN {
type master;
file "named.zero";
allow-update { none; };
};(g)
create a zone file internaldomain.local.zone file in /var/named/chroot/var/named like bellow:
$TTL 86400
@ IN SOA @ root (
42 ; serial (d. adams)
3H ; refresh
15M ; retry
1W ; expiry
1D ) ; minimum
IN NS internaldns
IN MX 10 internalmailserver
IN A 10.0.0.20
internaldns IN A 10.0.0.9
Account IN A 10.0.0.6
internalmailserver IN A 10.0.0.10
www IN A 10.0.0.20Note : make sure you have permission as bellow or bind would not be able to read it.
chown root:named internaldomain.local.zone
Primary Server:
(A)
Create zone entries in named.conf
Since This server will work as public dns server,We will create zone entries for example.co.uk under external views.
view "external"
{
/* This view will contain zones you want to serve only to "external" clients
* that have addresses that are not on your directly attached LAN interface subnets:
*/
match-clients { any; };
match-destinations { any; };
recursion no;
// you'd probably want to deny recursion to external clients, so you don't
// end up providing free DNS service to all takers
allow-query-cache { none; };
// Disable lookups for any cached data and root hints
// all views must contain the root hints zone:
include "/etc/named.root.hints";
// These are your "authoritative" external zones, and would probably
// contain entries for just your web and mail servers:
### Add Authoritiative zone for example.co.uk#######
zone "example.co.uk" IN {
type master;
file "example.co.uk.zone";
allow-update { none; };
allow-transfer { 22.33.44.55; };//only this host will received updates from this master server.
};
};Secondary Server :
Follow every steps from beginning . We just need to make changes on named.conf file to allow slave to download zone file, updates from master server.
view "external"
{
/* This view will contain zones you want to serve only to "external" clients
* that have addresses that are not on your directly attached LAN interface subnets:
*/
match-clients { any; };
match-destinations { any; };
recursion no;
// you'd probably want to deny recursion to external clients, so you don't
// end up providing free DNS service to all takers
allow-query-cache { none; };
// Disable lookups for any cached data and root hints
// all views must contain the root hints zone:
include "/etc/named.root.hints";
// These are your "authoritative" external zones, and would probably
// contain entries for just your web and mail servers:
### Add Authoritiative zone for example.co.uk#######
zone "example.co.uk" IN {
type slave;
file "slaves/example.co.uk.zone";
masters { 55.55.55.55 ;};
};
};Full named.conf file for Primary Name server(Public + Local host resolver :
cat named.conf
//
// Sample named.conf BIND DNS server 'named' configuration file
// for the Red Hat BIND distribution.
//
// See the BIND Administrator's Reference Manual (ARM) for details, in:
// file:///usr/share/doc/bind-*/arm/Bv9ARM.html
// Also see the BIND Configuration GUI : /usr/bin/system-config-bind and
// its manual.
//
options
{
// Those options should be used carefully because they disable port
// randomization
// query-source port 53;
// query-source-v6 port 53;
// Put files that named is allowed to write in the data/ directory:
directory "/var/named"; // the default
dump-file "data/cache_dump.db";
statistics-file "data/named_stats.txt";
memstatistics-file "data/named_mem_stats.txt";
};
logging
{
/* If you want to enable debugging, eg. using the 'rndc trace' command,
* named will try to write the 'named.run' file in the $directory (/var/nam ed).
* By default, SELinux policy does not allow named to modify the /var/named directory,
* so put the default debug log file in data/ :
*/
channel default_debug {
file "data/named.run";
severity dynamic;
};
};
//
// All BIND 9 zones are in a "view", which allow different zones to be served
// to different types of client addresses, and for options to be set for groups
// of zones.
//
// By default, if named.conf contains no "view" clauses, all zones are in the
// "default" view, which matches all clients.
//
// If named.conf contains any "view" clause, then all zones MUST be in a view;
// so it is recommended to start off using views to avoid having to restructure
// your configuration files in the future.
//
view "localhost_resolver"
{
/* This view sets up named to be a localhost resolver ( caching only nameserver ).
* If all you want is a caching-only nameserver, then you need only define this view:
*/
match-clients { localhost;10.0.0.0/24; };
match-destinations { localhost;10.0.0.0/24; };
recursion yes;
# all views must contain the root hints zone:
include "/etc/named.root.hints";
/* these are zones that contain definitions for all the localhost
* names and addresses, as recommended in RFC1912 - these names should
* ONLY be served to localhost clients:
*/
include "/etc/named.rfc1912.zones";
};
view "external"
{
/* This view will contain zones you want to serve only to "external" clients
* that have addresses that are not on your directly attached LAN interface subn ets:
*/
match-clients { any; };
match-destinations { any; };
recursion no;
// you'd probably want to deny recursion to external clients, so you don 't
// end up providing free DNS service to all takers
allow-query-cache { none; };
// Disable lookups for any cached data and root hints
// all views must contain the root hints zone:
include "/etc/named.root.hints";
// These are your "authoritative" external zones, and would probably
// contain entries for just your web and mail servers:
zone "example.co.uk" IN {
type master;
file "example.co.uk.zone";
allow-update { none; };
allow-transfer { 22.33.44.55; };//only this host will received updates from this master server.
};
};Full named.conf for Public Slave server
cat named.conf
//
// Sample named.conf BIND DNS server 'named' configuration file
// for the Red Hat BIND distribution.
//
// See the BIND Administrator's Reference Manual (ARM) for details, in:
// file:///usr/share/doc/bind-*/arm/Bv9ARM.html
// Also see the BIND Configuration GUI : /usr/bin/system-config-bind and
// its manual.
//
options
{
// Those options should be used carefully because they disable port
// randomization
// query-source port 53;
// query-source-v6 port 53;
// Put files that named is allowed to write in the data/ directory:
directory "/var/named"; // the default
dump-file "data/cache_dump.db";
statistics-file "data/named_stats.txt";
memstatistics-file "data/named_mem_stats.txt";
};
logging
{
/* If you want to enable debugging, eg. using the 'rndc trace' command,
* named will try to write the 'named.run' file in the $directory (/var/nam ed).
* By default, SELinux policy does not allow named to modify the /var/named directory,
* so put the default debug log file in data/ :
*/
channel default_debug {
file "data/named.run";
severity dynamic;
};
};
//
// All BIND 9 zones are in a "view", which allow different zones to be served
// to different types of client addresses, and for options to be set for groups
// of zones.
//
// By default, if named.conf contains no "view" clauses, all zones are in the
// "default" view, which matches all clients.
//
// If named.conf contains any "view" clause, then all zones MUST be in a view;
// so it is recommended to start off using views to avoid having to restructure
// your configuration files in the future.
//
view "localhost_resolver"
{
/* This view sets up named to be a localhost resolver ( caching only nameserver ).
* If all you want is a caching-only nameserver, then you need only define this view:
*/
match-clients { localhost;10.0.0.0/24; };
match-destinations { localhost;10.0.0.0/24; };
recursion yes;
# all views must contain the root hints zone:
include "/etc/named.root.hints";
/* these are zones that contain definitions for all the localhost
* names and addresses, as recommended in RFC1912 - these names should
* ONLY be served to localhost clients:
*/
include "/etc/named.rfc1912.zones";
};
view "external"
{
/* This view will contain zones you want to serve only to "external" clients
* that have addresses that are not on your directly attached LAN interface subn ets:
*/
match-clients { any; };
match-destinations { any; };
recursion no;
// you'd probably want to deny recursion to external clients, so you don 't
// end up providing free DNS service to all takers
allow-query-cache { none; };
// Disable lookups for any cached data and root hints
// all views must contain the root hints zone:
include "/etc/named.root.hints";
// These are your "authoritative" external zones, and would probably
// contain entries for just your web and mail servers:
zone "example.co.uk" IN {
type slave;
file "slaves/example.co.uk.zone";
masters { 55.55.55.55 ;};
};
};Securing Name server :
(a) Dont End up providing free dns service for every one
options {
recursion no;
};(b)
options {
fetch-glue no;
};(c)Allow zone transfer from specific host
### Add Authoritiative zone for example.co.uk#######
zone "example.co.uk" IN {
type master;
file "example.co.uk.zone";
allow-update { none; };
allow-transfer { 22.33.44.55; };//only this host will received updates from this master server.(d) Don’t disclose Bind version
options {
version "Not disclosed";
};Tags: how to configure bind dns server, How to configure linux dns server, how to configure linux public dns server