If hawkagent is no longer in the domain or is not active, it will still be shown as offline in the Hawk Web Console. If you are unable to follow the steps in the KB Article 000021745, the simplest way is to remove the Agent table in H2DB for persistent mode and remove entries from hawk_agents.xml for non-persistent mode.

If hawkagent is no longer in the domain or is not active , it will still be shown as offline in the Hawk Web Console.

All

For  Persistent Mode
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1). Start the H2 database using starth2db.bat or starth2db.sh and stop the webconsole if its running.

2). To connect H2 database web console server, fire http://:8082 URL in the web-browser.

3). In the connecting window. provide JDBC URL=jdbc:h2:~/hawk username=sa password= (should be similar to configured in webconsole\tomcat\webapps\hawkwebconsole\META-INF\context.xml)

4). Click the connect button.

5). You will see tables like AGENT, DASHBOARD_VIEW etc.

6). Run the following SQL to delete offline agents.
 
delete from repo where agent_id in (select agent_id from agent where status = 'N');
delete from agent where status = 'N';

7). Restart the Hawk webconsole.

For Step 6, you may manually edit these tables and delete the entries of your dismissed machines in the agent and repo table.
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For Non Persistent Mode
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If you are using a non-persistent setup, try to remove the corresponding entries in <HAWK_HOME>/webconsole/tomcat/AppData/hawk_agents.xml .  Restart the Web Console.
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