DATE :-- 02nd Sep 2014

Configuring DNS for resolving SCAN IP in VM

Step 1 :-- yum install dnsmasq

Step 2 :-- yum list dnsmasq

Step 3 :-- rpm -qa dnsmasq

Step 4 :-- Add IP to resolv.conf

cat /etc/resolv.conf
# Generated by NetworkManager
nameserver 127.0.0.1

On 127.0.0.1 dnsmasq service is running 

Step 5 :-- chattr +i /etc/resolv.conf

Step 6 :-- vi /etc/dnsmasq.conf

listen-address=192.168.56.166
port=53
no-resolv
domain-needed
bogus-priv
dns-forward-max=150
cache-size=1000
neg-ttl=3600
no-poll
no-hosts
add-hosts=/etc/racdns

Step 7 :-- vi /etc/racdns

192.168.56.151  rac12c-scan.localdomain   rac12c-scan
192.168.56.152  rac12c-scan.localdomain   rac12c-scan
192.168.56.153  rac12c-scan.localdomain   rac12c-scan
192.168.56.166  RAC112C.localdomain  RAC112C
192.168.0.122   RAC112C-vip.localdomain   RAC112C-vip
192.168.56.168  RAC212C.localdomain           RAC212C
192.168.0.132   RAC212C-vip.localdomain    RAC212C-vip

Step 8 :--  Testing nslookup

[root@RAC112C ~]# nslookup rac12c-scan

;; connection timed out; trying next origin

Server:  192.168.56.166

Address: 192.168.56.166#53

Name: rac12c-scan.localdomain

Address: 192.168.56.152

Name: rac12c-scan.localdomain

Address: 192.168.56.153

Name: rac12c-scan.localdomain

Address: 192.168.56.151

Note :-- SCAN entries in /etc/hosts needs to be commented out 

Every time VM is started .. dnsmasq services needs to be started to nslookup to work

service dnsmasq start