Sun Java System Application Server 9.1 High Availability Administration Guide

Adding Nodes

To increase processing and storage capacity of an HADB system, create new nodes and add them to the database.

After you add nodes, update the following properties of the HADB JDBC connection pool:

To add nodes, use the hadbm addnodes command. The command syntax is:

hadbm addnodes  [--no-refragment]  [--spares=sparecount]  
[--historypath=path]  
[--devicepath=path]  
[--set=attr-name-value-list]  
[--dbpassword=password | --dbpasswordfile=file ]  
[--adminpassword=password | --adminpasswordfile=file]  
--hosts=hostlist  [dbname]

The dbname operand specifies the database name. The default is hadb. The database must be in HAFaultTolerant or FaultTolerant state. For more information about database states, see Database States.

If you do not specify the --devicepath and --historypath options, the new nodes will have the same device path and use the same history files as the existing database.

Adding nodes performs a refragmentation and redistribution of the existing data to include the new nodes in the system. Online refragmenting requires that the disks for the HADB nodes have enough space to contain the old data and the new data simultaneously until refragmenting is finished, that is, the user data size must not exceed 50% of the space available for user data. For details, see Getting Device Information


Note –

The best time to add nodes is when the system is lightly loaded.



Example 3–13 Example of adding nodes

For example:

hadbm addnodes -adminpassword=password --hosts n6,n7,n8,n9

The following table describes the special hadbm addnodes command options. See General Options for a description of other options.

Table 3–13 hadbm addnodes Options

Option 

Description 

Default 

--no-refragment

-r 

Do not refragment the database during node creation; In this case, refragment the database later using the hadbm refragment command to use the new nodes. For details about refragmentation, see Refragmenting the Database

If you do not have sufficient device space for refragmentation, recreate the database with more nodes. See Adding Nodes by Recreating the Database

Not applicable 

--spares= number

-s 

Number of new spare nodes in addition to those that already exist. Must be even and not greater than the number of nodes added. 

--devicepath= path

-d 

Path to the devices. Devices are: 

  • DataDevice

  • NiLogDevice (node internal log device)

  • RelalgDevice (relational algebra query device)

    This path must already exist and be writable. To set this path differently for each node or each device, see Setting Heterogeneous Device Paths

Solaris and Linux: HADB_install_dir/device

Windows: C:\Sun\AppServer\SUNWhadb\vers, where vers is the HADB version number.

--hosts= hostlist

-H 

Comma-separated list of new host names for the new nodes in the database. One node is created for each comma-separated item in the list. The number of nodes must be even. IP addresses of HADB hosts must be IPv4 addresses. 

Using duplicate host names creates multiple nodes on the same machine with different port numbers. Make sure that nodes on the same machine are not mirror nodes. 

Odd numbered nodes are in one DRU, even numbered nodes in the other. If --spares is used, new spare nodes are those with the highest numbers.

If the database was created with double network interfaces, the new nodes must be configured in the same way. See Configuring Network Redundancy .

None