Home  >  Oracle Database Administration (DBA)  >  RAC  >  Adding a new node to an existing Oracle RAC

1. Configure the OS for the new node

• Install the OS (Linux in my case) with the same options as the other nodes

• Modify/ create the /etc/hosts on each node to have aliases for each node (rac1, rac1-priv, rac1-vip, rac2, ...)

• Verify/ Modify the following parameters in /etc/sysctl.conf :

# Default setting in bytes of the socket receive buffer
net.core.rmem_default=262144

# Default setting in bytes of the socket send buffer
net.core.wmem_default=262144

# Maximum socket receive buffer size which may be set by using
# the SO_RCVBUF socket option
net.core.rmem_max=262144

# Maximum socket send buffer size which may be set by using 
# the SO_SNDBUF socket option
net.core.wmem_max=262144

• Configure openfiler to add the rac3 node (the new node) and give permisions on crs & asm disks. Use service command to manage the iscsi server (on Openfiler server side):

[root@rac3 ~]# service iscsi-target status
ietd (pid 2914) is running...

                  [root@rac3 ~]# service iscsi-target restart 

• Configure the openfiler client: add the following line in the /etc/iscsi.conf on the node 3 (the new one) (openfiler1-priv is the alias for the openfiler IP):

                  . . .  

                  DiscoveryAddress=openfiler1-priv

                  . . . 

# service iscsi restart
Searching for iscsi-based multipath maps
Found 0 maps
Stopping iscsid: iscsid not running

Checking iscsi config:  [  OK  ]
Loading iscsi driver:  [  OK  ]
Starting iscsid: [  OK  ]

                 -- to activate the iscsi client when the system restart:

                 # chkconfig --level 345 iscsi on

• Create oracle user acount and dba group with gid and uid exactly like the other nodes

• Create the same CRS and ORACLE HOME give them the same right as on the other nodes

• Configure the kernel parameter & hangcheck-timer Kernel Module like on the other nodes

• Configure RAC Nodes for Remote Access (configure ssh or rsh )

• Restart the 3rd node and test if all is ok 

2. Add the node to the cluster

• Run the addNode.sh script from $ORA_CRS_HOME/oui/bin on one of the existing nodes as the oracle user

• The OUI Welcome screen will appear, click next

• Specify Cluster Nodes to Add to Installation

• The "Cluster Node Addition Progress" screen will appear. You will then be prompted to run rootaddnode.sh, orainstRoot.sh, root.sh as the root user

• After running the CRS root.sh on all new nodes, run $ORA_CRS_HOME/bin/racgons add_config <newnode1>:4948 <newnode2>:4948... from any node

• Next you will see the "End of Installation" screen. At this point you may exit the installer.

3. Add the RAC software to the new node

• On a pre-existing node run $ORACLE_HOME/oui/bin/addNode.sh script.

• The OUI Welcome screen will appear, click next

• On the "Specify Cluster Nodes to Add to Installation" screen, specify the node you want to add, click next

• The "Cluster Node Addition Summary" screen will appear, click next

• The "Cluster Node Addition Progress" screen will appear 

• You will then be prompted to run root.sh as the root user

• Next you will see the "End of Installation" screen. At this point you may exit the installer.

• run $ORACLE_HOME/bin/vipca -nodelist <newnode1>  (in my case is rac3)

• The VIPCA Welcome Screen will appear, click next

• Add the new node's virtual IP information, click next

• You will then see the "Summary" screen, click Install.

• You will now see a progress bar creating and starting the new CRS resources. Once this is finished, click ok, view the configuration results, and click on the exit button.

• Verify that interconnect information is correct with:

             oifcfg getif 

           If it is not correct, change it with: 

                oifcfg setif <interface-name>/<subnet>:<cluster_interconnect|public>

           For example: 

                 oifcfg setif -global eth1/10.10.10.0:cluster_interconnect 

            or 

                 oifcfg setif -node <nodename> eth1/10.10.10.0:cluster_interconnect

4. Reconfigure listeners for new node

• Run NETCA on the NEW node to verify that the listener is configured on the new node

• Choose "Cluster Configuration", click next

• Select all nodes, click next

• Choose "Listener configuration", click next.

• Choose "Reconfigure", click next

• Choose the listener you would like to reconfigure, click next

• Choose the protocol, click next

• Choose the correct port, click next

• Choose not to configure another listener

• If you get an error message saying, "The information provided for this listener is currently in use by another listener...". Click yes to continue anyway.

• The "Listener Configuration Complete" screen will appear, click next

• Click "Finish" to exit NETCA

• Run crs_stat to verify that the listener CRS resource was created. 

          Example: cd $ORA_CRS_HOME/bin ./crs_stat

• The new listener will likely be offline. Start it by starting the nodeapps on the new node. 

          Example: srvctl start nodeapps -n <newnode>

• Use crs_stat to confirm that all VIP's, GSD's, ONS's, and listeners are ONLINE.

5. Add instances via DBCA

More information about adding a node to an existing Oracle RAC you can get from  www.in-oracle.com