PostgreSQL Moves to Multiple Slaves

PostgreSQL to team with Lanux Ltd. to offer high-speed, hot-failover capabilities in its eRServer software.

PostgreSQL earlier this week released an update to eRServer that now supports multiple slaves in master-to-slave replications.

PostgreSQL Inc. CEO Geoff Davidson told eWEEK that Friday the company will announce that it is teaming with Lanux Ltd. to offer high-speed, hot-failover capabilities in its eRServer commercial replication software.

The high-availability technology from Lanux, of Toronto, will take advantage of servers running with replication. The new features are designed to automate warm failover so that system administrators dont have to intervene by flipping the switch on a warm server, said Davidson, also of Toronto. "This takes it from requiring fairly extensive intervention to allowing system administrators to properly automate a live, hot failover from one server to another," he said.

The Lanux/eRServer combination is also designed to deal with typical failover problems such as loss of transactions in process or those that have been processed but not committed to the master or other servers, Davidson said.

Copies of the eRServer 1.2 CD are now ready for existing Gold and Platinum Support clients to order and are available for new Gold or Platinum Support customers who sign up through PgSQL (click on "Support") or PostgreSQLs Certified Alliance Partners. Pricing is $9,995 for Gold Support customers and $19,995 for Platinum customers.

Multiple slaves are typically used for failover. Bruce Momjian, a lead developer for PostgreSQL, of Wolfville, Nova Scotia, said the move to multiple slaves is the first step in the open-source companys ultimate progression to multimaster replication. Such a setup would allow users to load balance and modify data on any server connected to the replication system--a feature that PostgreSQL hopes to include in PostgreSQL 7.5, expected in June or July 2003, said Momjian, in Philadelphia.

Other features in eRServer 1.2 include simplified installation and configuration, the ability to create database test environments, query distribution and load leveling, continuous or periodic replication, off-host processing, mirroring and disaster recovery, data merge between PostgreSQL installations, compatibility with most high-availability utilities, and warm failover switching.

(Editors Note: This story has been updated since its original posting to include pricing information.) (Editors Note: This story has been updated since its original posting to add new information about PostgreSQLs plans to team with Lanux Ltd.)