Tag Archives: Scan ip configure DNS

Configure DNS for SCAN IP in Oracle RAC

Configure DNS for SCAN IP in Oracle RAC with named service

Edit the hosts file present in Linux at /etc/hosts

[root@racnode1 named]# cat /etc/hosts
######-- SCAN IP -----############################
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1               localhost.localdomain localhost
::1             localhost6.localdomain6 localhost6
############--------------PUBLIC ------------ ###########
192.168.1.50      racnode1.india.com           racnode1
192.168.1.51      racnode2.india.com           racnode2
####### --------------------- VIP ------------------ ###########
10.10.10.10       racnode1-priv.india.com      racnode1-priv
10.10.10.20       racnode2-priv.india.com      racnode2-priv
####### ----------------  eth1 - PRIVATE ----------- ###########
192.168.1.60      racnode1-vip.india.com       racnode1-vip
192.168.1.61      racnode2-vip.india.com       racnode2-vip
#######################-- SCAN IP -----############################
192.168.1.70  racnodescan.india.com    racnodescan
192.168.1.71  racnodescan.india.com    racnodescan
192.168.1.72  racnodescan.india.com    racnodescan

Edit the named file for DNS Server

[root@racnode1 named]# pwd
/var/named/chroot/var/named

Create two file india.com.zone and 1.168.192.zone file as named or domain used in host file

[root@racnode1 named]# ls -ltr
total 24
drwxrwx--- 2 named named 4096 Jul 27  2004 slaves
drwxrwx--- 2 named named 4096 Aug 25  2004 data
-rw-r--r-- 1 root  root   700 Jul 16 09:05 india.com.zone
-rw-r--r-- 1 root  root   787 Jul 16 09:06 1.168.192.zone

Edit the two files as follows:

[root@racnode1 named]# more india.com.zone
$TTL    1d
india.com.  IN    SOA   lab-dns.india.com. root.india.com. (
100        ; se = serial number
8h         ; ref = refresh
5m         ; ret = update retry
3w         ; ex = expiry
3h         ; min = minimum
)

IN    NS    lab-dns.india.com.

; DNS server

lab-dns    IN    A    192.168.1.1

; RAC Nodes Public name

racnode1          IN    A    192.168.1.50
racnode2          IN    A    192.168.1.51
racnode2          IN    A    192.168.1.51

; RAC Nodes Public VIPs

racnode1-vip      IN    A    192.168.1.60
racnode2-vip      IN    A    192.168.1.61

; 3 SCAN VIPs

racnodescan       IN    A    192.168.1.70
racnodescan       IN    A    192.168.1.71
racnodescan       IN    A    192.168.1.72

[root@racnode1 named]# more 1.168.192.zone
$TTL    1d
@   IN    SOA   lab-dns.india.com. root.india.com. (
100        ; se = serial number
8h         ; ref = refresh
5m         ; ret = update retry
3w         ; ex = expiry
3h         ; min = minimum
)

IN    NS    lab-dns.india.com.

; DNS machine name in reverse
1        IN    PTR racnode.india.com.

; RAC Nodes Public Name in Reverse

50          IN    PTR racnode1.india.com.
51         IN    PTR racnode2.india.com.

; RAC Nodes Public VIPs in Reverse

60          IN    PTR      racnode1-vip.india.com.
61          IN    PTR      racnode2-vip.india.com.

; RAC Nodes SCAN VIPs in Reverse

70         IN    PTR      racnodescan.india.com.
71         IN    PTR      racnodescan.india.com.
72         IN    PTR      racnodescan.india.com.

configure named.conf file

[root@racnode1 etc]# pwd
/var/named/chroot/etc

[root@racnode1 etc]# ls
india.com.zone  localtime  named.conf  named.conf~  rndc.key

[root@racnode1 etc]# more named.conf
// Enterprise Linux BIND Configuration Tool
//
// Default initial “Caching Only” name server configuration
//

options {
directory “/var/named”;
dump-file “/var/named/data/cache_dump.db”;
statistics-file “/var/named/data/named_stats.txt”;
};

// Zone for this RAC configuration is hingu.net

zone “india.com” in {
type master;
file “india.com.zone”;
allow-update { none; };
};

// For reverse lookups

zone “1.168.192.in-addr.arpa” in {
type master;
file “1.168.192.zone”;
allow-update { none; };
};

include “/etc/rndc.key”;

Restart the named service for configure scan ip

[root@racnode1 etc]# start named service

then check the scan ip is resolved by named service.

nslookup racnodescan