CREATE LOAD BALANCE GROUP

Creates a group of network addresses that can be targeted by a load balancing routing rule. You create a group either using a list of network addresses, or basing it on one or more fault groups or subclusters.

Syntax

CREATE LOAD BALANCE GROUP group_name WITH {
      ADDRESS address[,...]
    | FAULT GROUP  fault_group[,...] FILTER 'IP_range'
    | SUBCLUSTER subcluster[,...] FILTER 'IP_range'
    }
    [ POLICY 'policy_setting' ]

Parameters

group_name

Name of the group to create. You use this name later when defining load balancing rules.

address[,...]

Comma-delimited list of network addresses you created earlier.

fault_group[,...]

Comma-delimited list of fault groups to use as the basis of the load balance group.

Note

Before you create your load balance group from a fault group, you must create network addresses on the nodes you want in your load balance group. Load balance groups only work with the network addresses you define on nodes, rather than IP addresses. See CREATE NETWORK ADDRESS.

subcluster[,...]

Comma-delimited list of subclusters to use as the basis of the load balance group.

Note

As with fault groups, you must create network addresses on the nodes in the subcluster you want to be part of the load balance group.

IP_range

Range of IP addresses in CIDR notation to include in the load balance group from the fault groups or subclusters. This range can be either IPv4 or IPv6. Only nodes that have a network address with an IP address that falls within this range are added to the load balancing group.

policy_setting

Determines how the initially-contacted node chooses a target from the group, one of the following:

• ROUNDROBIN (default) rotates among the available members of the load balancing group. The initially-contacted node keeps track of which node it chose last time, and chooses the next one in the cluster.

  Note

  Each node in the cluster maintains its own round-robin pointer that indicates which node it should pick next for each load-balancing group. Therefore, if clients connect to different initial nodes, they may be redirected to the same node.

• RANDOM chooses an available node from the group randomly.

• NONE disables load balancing.

Privileges

Examples

The following statement demonstrates creating a load balance group that contains several network addresses:

=> CREATE NETWORK ADDRESS addr01 ON v_vmart_node0001 WITH '10.20.110.21';
CREATE NETWORK ADDRESS
=> CREATE NETWORK ADDRESS addr02 ON v_vmart_node0002 WITH '10.20.110.22';
CREATE NETWORK ADDRESS
=> CREATE NETWORK ADDRESS addr03 on v_vmart_node0003 WITH '10.20.110.23';
CREATE NETWORK ADDRESS
=> CREATE NETWORK ADDRESS addr04 on v_vmart_node0004 WITH '10.20.110.24';
CREATE NETWORK ADDRESS
=> CREATE LOAD BALANCE GROUP group_1 WITH ADDRESS addr01, addr02;
CREATE LOAD BALANCE GROUP
=> CREATE LOAD BALANCE GROUP group_2 WITH ADDRESS addr03, addr04;
CREATE LOAD BALANCE GROUP

=> SELECT * FROM LOAD_BALANCE_GROUPS;
    name    |   policy   |     filter      |         type          | object_name
------------+------------+-----------------+-----------------------+-------------
 group_1    | ROUNDROBIN |                 | Network Address Group | addr01
 group_1    | ROUNDROBIN |                 | Network Address Group | addr02
 group_2    | ROUNDROBIN |                 | Network Address Group | addr03
 group_2    | ROUNDROBIN |                 | Network Address Group | addr04
(4 rows)

This example demonstrates creating a load balancing group using a fault group:

=> CREATE FAULT GROUP fault_1;
CREATE FAULT GROUP
=> ALTER FAULT GROUP fault_1 ADD NODE  v_vmart_node0001;
ALTER FAULT GROUP
=> ALTER FAULT GROUP fault_1 ADD NODE  v_vmart_node0002;
ALTER FAULT GROUP
=> ALTER FAULT GROUP fault_1 ADD NODE  v_vmart_node0003;
ALTER FAULT GROUP
=> ALTER FAULT GROUP fault_1 ADD NODE  v_vmart_node0004;
ALTER FAULT GROUP
=> SELECT node_name,node_address,node_address_family,export_address
   FROM v_catalog.nodes;
    node_name     | node_address | node_address_family | export_address
------------------+--------------+---------------------+----------------
 v_vmart_node0001 | 10.20.110.21 | ipv4                | 10.20.110.21
 v_vmart_node0002 | 10.20.110.22 | ipv4                | 10.20.110.22
 v_vmart_node0003 | 10.20.110.23 | ipv4                | 10.20.110.23
 v_vmart_node0004 | 10.20.110.24 | ipv4                | 10.20.110.24
(4 rows)

=> CREATE LOAD BALANCE GROUP group_all WITH FAULT GROUP fault_1 FILTER
   '0.0.0.0/0';
CREATE LOAD BALANCE GROUP

=> CREATE LOAD BALANCE GROUP group_some WITH FAULT GROUP fault_1 FILTER
   '10.20.110.21/30';
CREATE LOAD BALANCE GROUP

=> SELECT * FROM LOAD_BALANCE_GROUPS;
      name      |   policy   |     filter      |         type          | object_name
----------------+------------+-----------------+-----------------------+-------------
 group_all      | ROUNDROBIN | 0.0.0.0/0       | Fault Group           | fault_1
 group_some     | ROUNDROBIN | 10.20.110.21/30 | Fault Group           | fault_1
(2 rows)

See also

• ALTER LOAD BALANCE GROUP
• ALTER NETWORK ADDRESS
• ALTER ROUTING RULE
• LOAD_BALANCE_GROUPS
• NETWORK_ADDRESSES