DNS Server Installation in CentOS 6.5/6.4/6.3
ScenarioPrimary(Master) DNS Server Details:
Operating System : CentOS 6.5 server Hostname : masterdns.vpscheap.local IP Address : 192.168.1.100/24Secondary(Slave) DNS Server Details:
Operating System : CentOS 6.5 server Hostname : secondarydns.vpscheap.local IP Address : 192.168.1.101/24Client Details:
Operating System : CentOS 6.5 Desktop Hostname : Client.vpscheap.local IP Address : 192.168.1.102/24
Setup Primary(Master) DNS Server
[root@masterdns ~]# yum install bind* -y1. Configure DNS Server
Add the lines as shown below in ‘/etc/named.conf’ file
[root@masterdns ~]# vi /etc/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 { 127.0.0.1; 192.168.1.100; }; ### Master DNS IP ###
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; 192.168.1.0/24; }; ### IP Range ###
allow-transfer{ localhost; 192.168.1.101; }; ### Slave DNS IP ###
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";
};
zone"vpscheap.local" IN {
type master;
file "forward.vpscheap";
allow-update { none; };
};
zone"1.168.192.in-addr.arpa" IN {
type master;
file "reverse.vpscheap";
allow-update { none; };
};
include "/etc/named.rfc1912.zones";
include "/etc/named.root.key";
2. Create Zone files Create forward and reverse zone files which we mentioned in the ‘/etc/named.conf’ file.
2.1 Create Forward Zone
Create forward.vpscheap file in the ‘/var/named’ directory.
[root@masterdns ~]# vi /var/named/forward.vpscheap
$TTL 86400
@ IN SOA masterdns.vpscheap.local. root.vpscheap.local. (
2011071001 ;Serial
3600 ;Refresh
1800 ;Retry
604800 ;Expire
86400 ;Minimum TTL
)
@ IN NS masterdns.vpscheap.local.
@ IN NS secondarydns.vpscheap.local.
@ IN A 192.168.1.100
@ IN A 192.168.1.101
@ IN A 192.168.1.102
masterdns IN A 192.168.1.100
secondarydns IN A 192.168.1.101
client IN A 192.168.1.102
2.2 Create Reverse ZoneCreate reverse.vpscheap file in the ‘/var/named’ directory.
[root@masterdns ~]# vi /var/named/reverse.vpscheap
$TTL 86400
@ IN SOA masterdns.vpscheap.local. root.vpscheap.local. (
2011071001 ;Serial
3600 ;Refresh
1800 ;Retry
604800 ;Expire
86400 ;Minimum TTL
)
@ IN NS masterdns.vpscheap.local.
@ IN NS secondarydns.vpscheap.local.
@ IN PTR vpscheap.local.
masterdns IN A 192.168.1.100
secondarydns IN A 192.168.1.101
client IN A 192.168.1.102
100 IN PTR masterdns.vpscheap.local.
101 IN PTR secondarydns.vpscheap.local.
102 IN PTR client.vpscheap.local.
3. Start the DNS service
[root@masterdns ~]# service named start Starting named: [ OK ] [root@masterdns ~]# chkconfig named on4. Adjust iptables to allow DNS server from outside of the network
Add the lines as shown below in ‘/etc/sysconfig/iptables’ file.
[root@masterdns ~]# vi /etc/sysconfig/iptables # Firewall configuration written by system-config-firewall # Manual customization of this file is not recommended. *filter :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] -A INPUT -p udp -m state --state NEW --dport 53 -j ACCEPT -A INPUT -p tcp -m state --state NEW --dport 53 -j ACCEPT -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT -A INPUT -p icmp -j ACCEPT -A INPUT -i lo -j ACCEPT -A INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT -A INPUT -j REJECT --reject-with icmp-host-prohibited -A FORWARD -j REJECT --reject-with icmp-host-prohibited COMMIT5. Restart iptables
[root@masterdns ~]# service iptables restart iptables: Flushing firewall rules: [ OK ] iptables: Setting chains to policy ACCEPT: filter [ OK ] iptables: Unloading modules: [ OK ] iptables: Applying firewall rules: [ OK ]6. Test DNS configuration and zone files for any syntax errors
[root@masterdns ~]# named-checkconf /etc/named.conf [root@masterdns ~]# named-checkzone vpscheap.local /var/named/forward.vpscheap zone vpscheap.local/IN: loaded serial 2011071001 OK [root@masterdns ~]# named-checkzone vpscheap.local /var/named/reverse.vpscheap zone vpscheap.local/IN: loaded serial 2011071001 OK7. Test DNS Server
[root@masterdns ~]# dig masterdns.vpscheap.local ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.10.rc1.el6_3.6 <<>> masterdns.vpscheap.local ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 49834 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 1 ;; QUESTION SECTION: ;masterdns.vpscheap.local.INA ;; ANSWER SECTION: masterdns.vpscheap.local. 86400INA192.168.1.100 ;; AUTHORITY SECTION: vpscheap.local.86400INNSsecondarydns.vpscheap.local. vpscheap.local.86400INNSmasterdns.vpscheap.local. ;; ADDITIONAL SECTION: secondarydns.vpscheap.local. 86400 INA192.168.1.101 ;; Query time: 6 msec ;; SERVER: 192.168.1.100#53(192.168.1.100) ;; WHEN: Thu Mar 7 13:07:56 2013 ;; MSG SIZE rcvd: 114
[root@masterdns ~]# nslookup vpscheap.local Server:192.168.1.100 Address:192.168.1.100#53 Name:vpscheap.local Address: 192.168.1.102 Name:vpscheap.local Address: 192.168.1.100 Name:vpscheap.local Address: 192.168.1.101 Now the Primary DNS server is ready to use. Setup Secondary(Slave) DNS Server [root@secondarydns ~]# yum install bind* -y1. Configure Slave DNS Server
Open the main configuration file ‘/etc/named.conf’ and add the lines as shown below.
[root@secondarydns ~]# vi /etc/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 { 127.0.0.1; 192.168.1.101; };
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; 192.168.1.0/24; };
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";
};
zone"vpscheap.local" IN {
type slave;
file "slaves/vpscheap.fwd";
masters { 192.168.1.100; };
};
zone"1.168.192.in-addr.arpa" IN {
type slave;
file "slaves/vpscheap.rev";
masters { 192.168.1.100; };
};
include "/etc/named.rfc1912.zones";
include "/etc/named.root.key";
2. Start the DNS Service
[root@secondarydns ~]# service named start Generating /etc/rndc.key: [ OK ] Starting named: [ OK ] [root@secondarydns ~]# chkconfig named onNow the forward and reverse zones are automatically replicated from Master DNS server to ‘/var/named/slaves/’ in Secondary DNS server.
[root@secondarydns ~]# ls /var/named/slaves/ vpscheap.fwd vpscheap.rev [root@secondarydns ~]# cat /var/named/slaves/vpscheap.fwd $ORIGIN . $TTL 86400; 1 day vpscheap.localIN SOAmasterdns.vpscheap.local. root.vpscheap.local. ( 2011071001 ; serial 3600 ; refresh (1 hour) 1800 ; retry (30 minutes) 604800 ; expire (1 week) 86400 ; minimum (1 day) ) NS masterdns.vpscheap.local. NS secondarydns.vpscheap.local. A192.168.1.100 A192.168.1.101 A192.168.1.102 $ORIGIN vpscheap.local. clientA192.168.1.102 masterdnsA192.168.1.100 secondarydnsA192.168.1.101 [root@secondarydns ~]# cat /var/named/slaves/vpscheap.rev $ORIGIN . $TTL 86400; 1 day 1.168.192.in-addr.arpaIN SOAmasterdns.vpscheap.local. root.vpscheap.local. ( 2011071001 ; serial 3600 ; refresh (1 hour) 1800 ; retry (30 minutes) 604800 ; expire (1 week) 86400 ; minimum (1 day) ) NS masterdns.vpscheap.local. NS secondarydns.vpscheap.local. PTRvpscheap.local. $ORIGIN 1.168.192.in-addr.arpa. 100PTRmasterdns.vpscheap.local. 101PTRsecondarydns.vpscheap.local. 102PTRclient.vpscheap.local. clientA192.168.1.102 masterdnsA192.168.1.100 secondarydnsA192.168.1.1013. Add the DNS Server details to all systems
[root@secondarydns ~]# vi /etc/resolv.conf # Generated by NetworkManager search ostechnix.com nameserver 192.168.1.100 nameserver 192.168.1.101 nameserver 8.8.8.84. Test DNS Server
[root@secondarydns ~]# dig masterdns.vpscheap.local ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.10.rc1.el6_3.6 <<>> masterdns.vpscheap.local ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 21487 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 1 ;; QUESTION SECTION: ;masterdns.vpscheap.local.INA ;; ANSWER SECTION: masterdns.vpscheap.local. 86400INA192.168.1.100 ;; AUTHORITY SECTION: vpscheap.local.86400INNSmasterdns.vpscheap.local. vpscheap.local.86400INNSsecondarydns.vpscheap.local. ;; ADDITIONAL SECTION: secondarydns.vpscheap.local. 86400 INA192.168.1.101 ;; Query time: 15 msec ;; SERVER: 192.168.1.100#53(192.168.1.100) ;; WHEN: Thu Mar 7 13:27:57 2013 ;; MSG SIZE rcvd: 114 [root@secondarydns ~]# dig secondarydns.vpscheap.local ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.10.rc1.el6_3.6 <<>> secondarydns.vpscheap.local ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 20958 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 1 ;; QUESTION SECTION: ;secondarydns.vpscheap.local.INA ;; ANSWER SECTION: secondarydns.vpscheap.local. 86400 INA192.168.1.101 ;; AUTHORITY SECTION: vpscheap.local.86400INNSmasterdns.vpscheap.local. vpscheap.local.86400INNSsecondarydns.vpscheap.local. ;; ADDITIONAL SECTION: masterdns.vpscheap.local. 86400INA192.168.1.100 ;; Query time: 4 msec ;; SERVER: 192.168.1.100#53(192.168.1.100) ;; WHEN: Thu Mar 7 13:31:53 2013 ;; MSG SIZE rcvd: 114 [root@secondarydns ~]# nslookup vpscheap.local Server:192.168.1.100 Address:192.168.1.100#53 Name:vpscheap.local Address: 192.168.1.101 Name:vpscheap.local Address: 192.168.1.102 Name:vpscheap.local Address: 192.168.1.100
Client Side Configuration
Add the DNS server details in ‘/etc/resolv.conf’ file in all client systems[root@client vpscheap]# vi /etc/resolv.conf # Generated by NetworkManager search vpscheap.local nameserver 192.168.1.100 nameserver 192.168.1.101 nameserver 8.8.8.8Test DNS Server
[root@client vpscheap]# dig masterdns.vpscheap.local ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.10.rc1.el6 <<>> masterdns.vpscheap.local ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 19496 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 1 ;; QUESTION SECTION: ;masterdns.vpscheap.local.INA ;; ANSWER SECTION: masterdns.vpscheap.local. 86400INA192.168.1.100 ;; AUTHORITY SECTION: vpscheap.local.86400INNSmasterdns.vpscheap.local. vpscheap.local.86400INNSsecondarydns.vpscheap.local. ;; ADDITIONAL SECTION: secondarydns.vpscheap.local. 86400 INA192.168.1.101 ;; Query time: 30 msec ;; SERVER: 192.168.1.100#53(192.168.1.100) ;; WHEN: Thu Mar 7 13:47:55 2013 ;; MSG SIZE rcvd: 114 [root@client vpscheap]# dig secondarydns.vpscheap.local ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.10.rc1.el6 <<>> secondarydns.vpscheap.local ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 14852 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 1 ;; QUESTION SECTION: ;secondarydns.vpscheap.local.INA ;; ANSWER SECTION: secondarydns.vpscheap.local. 86400 INA192.168.1.101 ;; AUTHORITY SECTION: vpscheap.local.86400INNSsecondarydns.vpscheap.local. vpscheap.local.86400INNSmasterdns.vpscheap.local. ;; ADDITIONAL SECTION: masterdns.vpscheap.local. 86400INA192.168.1.100 ;; Query time: 8 msec ;; SERVER: 192.168.1.100#53(192.168.1.100) ;; WHEN: Thu Mar 7 13:48:38 2013 ;; MSG SIZE rcvd: 114 [root@client vpscheap]# dig client.vpscheap.local ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.10.rc1.el6 <<>> client.vpscheap.local ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 14604 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2 ;; QUESTION SECTION: ;client.vpscheap.local.INA ;; ANSWER SECTION: client.vpscheap.local.86400INA192.168.1.102 ;; AUTHORITY SECTION: vpscheap.local.86400INNSmasterdns.vpscheap.local. vpscheap.local.86400INNSsecondarydns.vpscheap.local. ;; ADDITIONAL SECTION: masterdns.vpscheap.local. 86400INA192.168.1.100 secondarydns.vpscheap.local. 86400 INA192.168.1.101 ;; Query time: 5 msec ;; SERVER: 192.168.1.100#53(192.168.1.100) ;; WHEN: Thu Mar 7 13:49:11 2013 ;; MSG SIZE rcvd: 137 [root@client vpscheap]# nslookup vpscheap.local Server:192.168.1.100 Address:192.168.1.100#53 Name:vpscheap.local Address: 192.168.1.102 Name:vpscheap.local Address: 192.168.1.100 Name:vpscheap.local Address: 192.168.1.101Now the primary and secondary DNS servers are ready.
