Skip to Content
Tomcat: The Definitive Guide, 2nd Edition
book

Tomcat: The Definitive Guide, 2nd Edition

by Jason Brittain, Ian F. Darwin
October 2007
Intermediate to advanced
496 pages
16h 50m
English
O'Reilly Media, Inc.
Content preview from Tomcat: The Definitive Guide, 2nd Edition

JDBC Request Distribution and Failover

Typical relational database configurations have one database server instance running on one server computer. Even if all of the other components of the system are clustered, a single database server instance could crash and cause the entire site running on the cluster to become unusable. So, some sort of clustering must also be done for the database so it is not a single point of failure.

There are relational database servers that support replication but not parallel use and some that support both replication and parallel use.

In the case where the database supports replication but not parallelization, the database instance that is replicated to becomes a secondary server that the cluster could failover to. In this case, the database driver code (commonly a JDBC driver) would need to know how to connect to each database instance and when to failover to a secondary (replicated) server.

In the case where the database supports parallelization, the database driver could load balance across several database server instances and detect failures. Here are some products and projects that might interest you:

Oracle RAC

One commercial parallel relational database server implementation is Oracle Corporation's Oracle 10g Real Application Clusters (RAC). See http://www.oracle.com/database/rac_home.html for product information.

Sequoia: Open source JDBC replication and load balancing (formerly C-JDBC)

This interesting open source project has set out to make JDBC ...

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.

Read now

Unlock full access

More than 5,000 organizations count on O’Reilly

AirBnbBlueOriginElectronic ArtsHomeDepotNasdaqRakutenTata Consultancy Services

QuotationMarkO’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.
Julian F.
Head of Cybersecurity
QuotationMarkI wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.
Addison B.
Field Engineer
QuotationMarkI’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.
Amir M.
Data Platform Tech Lead
QuotationMarkI'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Mark W.
Embedded Software Engineer

You might also like

Learning Apache Tomcat

Learning Apache Tomcat

Martin Kalin
Head First Servlets and JSP, 2nd Edition

Head First Servlets and JSP, 2nd Edition

Bryan Basham, Kathy Sierra, Bert Bates
Modern Java in Action

Modern Java in Action

Alan Mycroft, Mario Fusco, Raoul-Gabriel Urma
Java 8 in Action

Java 8 in Action

Alan Mycroft, Mario Fusco, Raoul-Gabriel Urma

Publisher Resources

ISBN: 9780596101060Errata