JVM caches IP addresses, ignores DNS changes on Solaris Operating System
 Technote (troubleshooting)
 
Problem(Abstract)
The JVM™ has the ability to indefinitely cache IP addresses that are accessed within an application running on the IBM® WebSphere® Application Server. This causes a problem in specific cases when a DNS entry is changed, but because of the cache, the application continues to access the previous IP of a DNS entry. The cache is refreshed only on restart of the Application Server (JVM).
 
Cause
IP address stored in cache is outdated.
 
Resolving the problem
A refresh-rate parameter can be set for this cache as follows:
sun.net.inetaddr.ttl=<time in seconds>

After the specified number of seconds passes, the cache is refreshed and then picks up any changes made to the DNS. This allows an application to go to the correct IP.

Add this parameter as a command line property by preceding it with a -D on the Application Server running the application in question.

This documentation is for JDK™ 1.4, currently used only by V5.0 release clients; however, most of it applies to 1.3.0 and 1.3.1 as well. See the Sun documentation regarding these properties for additional information:

http://java.sun.com/products/archive/j2se/1.4.1_07/index.html
 
Related information
Sun documentation
 
 
Cross Reference information
Segment Product Component Platform Version Edition
Application Servers Runtimes for Java Technology Java SDK
 
 


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server > Java SDK
Operating system(s): Windows
Software version: 5.1
Software edition:
Reference #: 1121439
IBM Group: Software Group
Modified date: Sep 15, 2004