How to update the IP address of the SCAN VIP resources (Doc ID 952903.1)

APPLIES TO:

Oracle Database - Enterprise Edition - Version 11.2.0.1 to 11.2.0.4 [Release 11.2]
Information in this document applies to any platform.

GOAL

The purpose of this document is to explain how to change the IP addresses associated with the  VIPs in a 11gR2 Grid (CRS) environment. 

The IP addresses associated with the SCAN VIP resources are initially set when the SCAN resources are created. 
Any changes to the DNS entry for the SCAN are not automatically propagated to the clusterware and need to be done manually.

This applies only to installations that are not using .

The information in this note can also be helpful in cases where SCAN was originally configured with just one address and is now being expanded to accommodate three IP addresses.

SOLUTION

1. Before the SCAN VIPs can be changed, the entry for the SCAN name on the Domain Name Server (DNS) needs to be updated with the new IP addresses. This usually will be done by a network administrator. To check the current setting, the following command can be used:
   
   nslookup 
2. To check the current IP address(es) of the SCAN VIPs, run the following commands as the root user:
   $GRID_HOME/bin/srvctl config scan
3. Stop the SCAN listeners and SCAN
   $GRID_HOME/bin/srvctl stop scan_listener 
   $GRID_HOME/bin/srvctl stop scan
4. Next refresh the SCAN VIPs with the new IP addresses from the DNS entry:
   $GRID_HOME/bin/srvctl modify scan -n 
5. To check if the SCAN VIPs have been changed, run the following command, it should now show the new IP addresses.
   $GRID_HOME/bin/srvctl config scan
6. Restart SCAN & SCAN listener:
   $GRID_HOME/bin/srvctl start scan 
   $GRID_HOME/bin/srvctl start scan_listener
    
7. If the number of SCAN VIPs has changed, the SCAN listener needs to be updated:
   
   $GRID_HOME/bin/srvctl modify scan_listener -u
    

Below is an example using the following configuration:

• The name of the SCAN is sales-scan.example.com
• subnet of the public network is 10.100.10.0
• netmask for the public network is 255.255.255.0
• name of the public interface is eth1
• old IP addresses: 10.100.10.81, 10.100.10.82 & 10.100.10.83
• new IP addresses: 10.100.10.121, 10.100.10.122 & 10.100.10.123

Stopping & starting the SCAN VIPs/listeners can be done by the grid user, however the 'srvctl modify scan' command must be executed by root user, so it's practical to execute all steps as the root user.

A lookup of the SCAN on the DNS server shows that the entry has already been updated with the new IP addresses:

$ nslookup sales-scan.example.com 
Server:         dns1.example.com
Address:        10.100.10.70#53

Name:   sales-scan.example.com
Address: 10.100.10.123
Name:   sales-scan.example.com
Address: 10.100.10.122
Name:   sales-scan.example.com
Address: 10.100.10.121

Stop the SCAN listener and the SCAN VIP resources:

# $GRID_HOME/bin/srvctl stop scan_listener
# $GRID_HOME/bin/srvctl stop scan
# $GRID_HOME/bin/srvctl status scan
SCAN VIP scan1 is enabled
SCAN VIP scan1 is not running
SCAN VIP scan2 is enabled
SCAN VIP scan2 is not running
SCAN VIP scan3 is enabled
SCAN VIP scan3 is not running
# $GRID_HOME/bin/srvctl status scan_listener
SCAN Listener LISTENER_SCAN1 is enabled
SCAN listener LISTENER_SCAN1 is not running
SCAN Listener LISTENER_SCAN2 is enabled
SCAN listener LISTENER_SCAN2 is not running
SCAN Listener LISTENER_SCAN3 is enabled
SCAN listener LISTENER_SCAN3 is not running

The SCAN VIP resources still show the old IP addresses:

# $GRID_HOME/bin/srvctl config scan
SCAN name: sales-scan, Network: 1/10.100.10.0/255.255.255.0/eth1
SCAN VIP name: scan1, IP: /sales-scan.example.com/10.100.10.81
SCAN VIP name: scan2, IP: /sales-scan.example.com/10.100.10.82
SCAN VIP name: scan3, IP: /sales-scan.example.com/10.100.10.83

Now tell CRS to update the SCAN VIP resources:

# $GRID_HOME/bin/srvctl modify scan -n sales-scan.example.com

To verify that the change was successful, check the SCAN configuration again:

# $GRID_HOME/bin/srvctl config scan
SCAN name: sales-scan, Network: 1/10.100.10.0/255.255.255.0/eth1
SCAN VIP name: scan1, IP: /sales-scan.example.com/10.100.10.121
SCAN VIP name: scan2, IP: /sales-scan.example.com/10.100.10.122
SCAN VIP name: scan3, IP: /sales-scan.example.com/10.100.10.123

 
Start SCAN and the SCAN listener:

# $GRID_HOME/bin/srvctl start scan
# $GRID_HOME/bin/srvctl start scan_listener

Please note that if the SCAN VIPs are being changed because of a change of the subnet  of the public network additional changes may be required , e.g. the node VIPs and the network resource  For more information please refer to Document 276434.1 and the 11.2 documentation.