Oracle Clusterware R2 Scan DNS

So how does it work:

First, my (named, linux) DNS is running on 10.161.102.40.
This DNS does the naming for cluster01.nl.oracle.com and pts.local.
For cluster01.nl.oracle.com a "delegation" is made, so that every request to a machine in the domain .cluster01.nl.oracle.com is delegated to the GNS. (with the GNS VIP).

In DNS:

cluster01.nl.oracle.com NS gns.cluster01.nl.oracle.com
gns.cluster01.nl.oracle.com. 10.161.102.55
So, once the cluster installation is done, the GNS in the cluster will be stared and a request to scan.cluster01.nl.oracle.com will be forwarded to the GNS. The GNS will then take care of the request and answer which three nodes in the cluster will serve as scan listeners:

[root@gridnode01pts05 ~]# nslookup scan.cluster01.nl.oracle.com
Server: 10.161.102.40
Address: 10.161.102.40#53
Non-authoritative answer:
Name: scan.cluster01.nl.oracle.com
Address: 10.161.102.78
Name: scan.cluster01.nl.oracle.com
Address: 10.161.102.79
Name: scan.cluster01.nl.oracle.com
Address: 10.161.102.77
Also, with dig, you can see all information coming from GNS:

[root@dns-dhcp ~]# dig scan.cluster01.nl.oracle.com
; <<>> DiG 9.3.4-P1 <<>> scan.cluster01.nl.oracle.com
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 46016
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 10, ADDITIONAL: 10
;; QUESTION SECTION:
;scan.cluster01.nl.oracle.com. IN A
;; ANSWER SECTION:
scan.cluster01.nl.oracle.com. 6 IN A 10.161.102.78
scan.cluster01.nl.oracle.com. 6 IN A 10.161.102.79
scan.cluster01.nl.oracle.com. 6 IN A 10.161.102.77
;; AUTHORITY SECTION:
oracle.com. 10732 IN NS dns2.us.oracle.com.
oracle.com. 10732 IN NS dns3.us.oracle.com.
oracle.com. 10732 IN NS dns4.us.oracle.com.
oracle.com. 10732 IN NS dns1-us.us.oracle.com.
oracle.com. 10732 IN NS dnsmaster1.oracle.com.
oracle.com. 10732 IN NS dnsmaster2.oracle.com.
oracle.com. 10732 IN NS dnsmaster3.oracle.com.
oracle.com. 10732 IN NS dnsmaster4.oracle.com.
oracle.com. 10732 IN NS dnsmaster5.oracle.com.
oracle.com. 10732 IN NS dnsmaster6.oracle.com.
;; ADDITIONAL SECTION:
dns2.us.oracle.com. 3984 IN A 130.35.249.52
dns3.us.oracle.com. 3984 IN A 144.20.190.70
dns4.us.oracle.com. 3984 IN A 138.2.202.15
dns1-us.us.oracle.com. 3984 IN A 130.35.249.41
dnsmaster1.oracle.com. 1060 IN A 192.135.82.4
dnsmaster2.oracle.com. 1060 IN A 192.135.82.20
dnsmaster3.oracle.com. 1060 IN A 192.135.82.36
dnsmaster4.oracle.com. 1060 IN A 192.135.82.52
dnsmaster5.oracle.com. 1060 IN A 192.135.82.70
dnsmaster6.oracle.com. 1060 IN A 192.135.82.84
;; Query time: 0 msec
;; SERVER: 10.161.102.40#53(10.161.102.40)
;; WHEN: Sat Sep 19 17:15:47 2009
;; MSG SIZE rcvd: 486

Later, when the database is installed, you can use the SCAN with SQLNet EZ connect to connect to the database. Can't wait, I just have to demo it now:

[oracle@gridnode01pts05 ~]$ sqlplus system/oracle@scan.cluster01.nl.oracle.com:1521/dbpts05.pts.local
SQL*Plus: Release 11.2.0.1.0 Production on Sat Sep 19 17:11:32 2009
Copyright (c) 1982, 2009, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Data Mining and Real Application Testing options
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