Configuring core group IP caching

The caching of name-to-IP address information can be performed at many levels within the network communication software stack. These levels include within the operating system, the Java virtual machine, and within WebSphere Application Server components, such as core groups. Core groups use caching to reduce the overhead that is associated with IP address name lookup. We can adjust the interval at which a core group IP cache is cleared.

 

Before you begin

By default, a core group cache is cleared every 60 minutes. We can determine the correct time interval for your environment.

 

About this task

You want to change the length of time that IP addresses are retained in a core group cache.

To change how frequently a core group cache is cleared:

 

Procedure

1. In the administrative console, click Servers > Core groups > Core group settings > core_group_name.

2. Under Additional Properties, click Custom Properties.

3. Change the value that is specified for the IBM_CS_IP_REFRESH_MINUTES custom property. A core group cache cannot be cleared more frequently then once a minute.

   If the IBM_CS_IP_REFRESH_MINUTES property already exists, click on the property name and in the Value field, specify the length of time, in minutes, you want to wait before a core group cache is cleared.

   If this property does not already exist, click New and create it:

   1. In the Name field, specify IBM_CS_IP_REFRESH_MINUTES.

   2. In the Value field specify the length of time, in minutes, that you want to wait before a core group cache is cleared.

4. Click OK, and then click Save to save your changes.

5. Select Synchronize changes with nodes, and then click Save again.

6. Restart all members of the core group.

 

Results

After the servers restart, all of the core group members run with the new discovery protocol setting.

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Related concepts
Core groups (high availability domains) Related tasks
Setting up a high availability environment

 

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