Before start, I configured this based on other examples on web and I am configuring to being use for Single Client Access Name (SCAN) on Oracle RAC configuration. This DNS configuration is for a test environment, this is for make SCAN work. if you are using virtual machines I recommend you to install the DNS on separete virtual machine or your host machine.
I am using example.com domain so if you are using different domain or localhost you have to change according to your DNS configuration files.
DNS Installation
[root@dns ~]# yum install bind-libs bind bind-utils -y
DNS Configuration files
Now we have to configure the following files
- DNS configuration file
/etc/named.conf - domain zone file
/var/named/example.com.zone - reverse dns zone file
/var/named/1.168.192.in-addr.arpa - Resolv file
/etc/resolv.conf
/etc/named.conf
[root@dns ~]# cat /etc/named.conf options { listen-on port 53 { 127.0.0.1; 192.168.1.175; }; 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; 192.168.0.0; }; recursion yes; dnssec-enable yes; dnssec-validation yes; /* Path to ISC DLV key */ bindkeys-file "/etc/named.iscdlv.key"; managed-keys-directory "/var/named/dynamic"; forwarders { 8.8.8.8; 8.8.4.4; }; }; logging { channel default_debug { file "data/named.run"; severity dynamic; }; }; zone "example.com" IN { type master; file "example.com.zone"; allow-update { none; }; }; zone "1.168.192.in-addr.arpa." IN { type master; file "1.168.192.in-addr.arpa"; allow-update { none; }; }; include "/etc/named.rfc1912.zones"; include "/etc/named.root.key";
/var/named/example.com.zone
description of the IPs to be configure in this file
Public | ||
192.168.1.101 | host01.example.com | host01 |
192.168.1.102 | host02.example.com | host02 |
192.168.1.103 | host03.example.com | host03 |
Private | ||
192.168.2.101 | host01-priv1.example.com | host01-priv1 |
192.168.2.102 | host02-priv1.example.com | host02-priv1 |
192.168.2.103 | host03-priv1.example.com | host03-priv1 |
192.168.2.121 | host01-priv2.example.com | host01-priv2 |
192.168.2.122 | host02-priv2.example.com | host02-priv2 |
192.168.2.123 | host03-priv2.example.com | host03-priv2 |
Virtual | ||
192.168.1.111 | host01-vip.example.com | host01-vip |
192.168.1.112 | host02-vip.example.com | host02-vip |
192.168.1.113 | host03-vip.example.com | host03-vip |
SCAN | ||
192.168.1.121 | cluster01-scan.example.com | cluster01-scan |
192.168.1.122 | cluster01-scan.example.com | cluster01-scan |
192.168.1.123 | cluster01-scan.example.com | cluster01-scan |
[root@dns ~]# cat /var/named/example.com.zone $TTL 86400 @ IN SOA dns.example.com. root.example.com.( 42 ; serial (d. adams) 3H ; refresh 15M ; retry 1W ; expiry 1D ) ; minimum IN NS dns.example.com. dns IN A 192.168.1.175 host01 IN A 192.168.1.101 host02 IN A 192.168.1.102 host03 IN A 192.168.1.103 host01-priv1 IN A 192.168.2.101 host02-priv1 IN A 192.168.2.102 host03-priv1 IN A 192.168.2.103 host01-priv2 IN A 192.168.2.121 host02-priv2 IN A 192.168.2.122 host03-priv2 IN A 192.168.2.123 host01-vip IN A 192.168.1.111 host02-vip IN A 192.168.1.112 host03-vip IN A 192.168.1.113 cluster01-scan IN A 192.168.1.121 cluster01-scan IN A 192.168.1.122 cluster01-scan IN A 192.168.1.123
/var/named/1.168.192.in-addr.arpa
[root@dns ~]# cat /var/named/1.168.192.in-addr.arpa $TTL 1H @ IN SOA dns.example.com. root.dns.example.com. ( 2 3H 1H 1W 1H ) 1.168.192.in-addr.arpa. IN NS dns.example.com. 101 IN PTR host01.example.com. 102 IN PTR host02.example.com. 103 IN PTR host03.example.com. 111 IN PTR host01-vip.example.com. 112 IN PTR host02-vip.example.com. 113 IN PTR host03-vip.example.com. 121 IN PTR cluster01-scan.example.com. 122 IN PTR cluster01-scan.example.com. 123 IN PTR cluster01-scan.example.com.