In Directory Proxy Server 5, the ids-proxy-sch-LoadBalanceProperty is used to configure load balancing across multiple LDAP servers. Directory Proxy Server 5 supports proportional load balancing only, that is, each LDAP server is allotted a certain percentage of the total load. The ids-proxy-sch-LoadBalanceProperty object class has one attribute, ids-proxy-con-Server, whose value has the following syntax:
In Iplanet Directory Access Router 5.0 (IDAR) these configuration attributes are stored under ids-proxy-con-Name=load-balance,ou=properties,ou=pd2,ou=iDAR,o=services. In Directory Proxy Server 5.2, these configuration attributes are stored under ids-proxy-con-name=load-balancing-1,ou=properties,cn=user-defined-name,ou=dar-config,o=NetscapeRoot.
In Directory Proxy Server 6.0, load balancing is configured as a property of a data source pool. A data source pool is essentially a collection of LDAP servers to which Directory Proxy Server can route requests. For information about setting up a data source pool, see Creating and Configuring LDAP Data Source Pools in Sun Java System Directory Server Enterprise Edition 6.0 Administration Guide. For a list of properties associated with a data source pool, run the following command:
$ dpconf help-properties | grep ldap-data-source-pool
Directory Proxy Server 6.0 supports proportional load balancing but also supports additional load balancing algorithms. To configure proportional load balancing, set the property of the data source pool as follows:
$ dpconf set-ldap-data-source-pool-prop data-source-pool-name load-balancing-algorithm:proportional
The percentage of load allotted to each server is configured by setting various properties of an attached data source. An attached data source is a data source that has been attached to a specific data source pool. To configure proportional load, set the weight properties of the attached data source for each operation type as follows:
$ dpconf set-attached-ldap-data-source-prop data-source-pool-name attached-data-source-name add-weight:value bind-weight:value compare-weight:value delete-weight:value modify-dn-weight:value modify-weight:value search-weight:value
For more information, see Configuring Load Balancing in Sun Java System Directory Server Enterprise Edition 6.0 Administration Guide.
To monitor the state of its backend LDAP servers, Directory Proxy Server 5 performs an anonymous search operation on the RootDSE of each server every ten seconds. Directory Proxy Server 6.0 has a number of properties that can be configured to monitor its backend servers. For more information, see Retrieving Monitored Data About Data Sources in Sun Java System Directory Server Enterprise Edition 6.0 Administration Guide.