Sun Java System Messaging Server 6.3 Administration Guide

3.2.4 Choosing a High Availability Model

The following table summarizes the advantages and disadvantages of each high availability model. Use this information to help you determine which model is right for your deployment.

Table 3–1 HA Model Comparison




Recommended Users 


  • Simple Configuration

  • Backup node is 100 percent reserved

Machine resources are not fully utilized. 

A small service provider with plans to expand in the future 


  • Better use of system resources

  • Higher availability

Resource contention on the backup node.  

HA requires fully redundant disks. 

A small corporate deployment that can accept performance penalties in the event of a single server failure 

N + 1 

  • Load distribution

  • Easy expansion

Management and configuration complexity. 

A large service provider who requires distribution with no resource constraints