Fix the Snow Commander Service Portal “503 Service Unavailable” error
The Commander Service Portal may become unresponsive and display a
503 Service Unavailable error, affecting portal performance and maintenance operations. This error is typically linked to filters in the request processing chain that do not support asynchronous operations and appears in logs as:The error in the logs typically appears as:
catalina.connector.Request - Unable to start async because the following classes in the processing chain do not support async [org.tuckey.web.filters.urlrewrite.UrlRewriteFilter, com.embotics.portal.security.SecurityHeaderFilter]
Follow the steps below to apply a fix and restore normal portal functionality.
-
Stop the Commander service
- On the application server, open the Windows Start menu.
- In the Snow Software program group, select Control Panel.
- In the Snow Software Control Panel, open the Service Control tab and select Services to launch the Windows Services console.
- Locate the Commander service, select it, and then click Stop.
- Verify that the service is no longer running.
-
Modify the
web.xmlfile- Navigate to:
C:\Program Files\Embotics\Commander\tomcat\webapps\portal\WEB-INF\web.xml
- Navigate to:
-
- Add the following line to the relevant filter entries:
<async-supported>true</async-supported>Apply these changes to:- SecurityHeaderFilter (around line 132)
- UrlRewriteFilter (around line 148)
- Add the following line to the relevant filter entries:
-
Verify the changes
- Check that the
web.xmlfile includes<async-supported>true</async-supported>for both filters as shown in the structure above.
- Check that the
-
Restart the Commander service
- Start the Commander service from the Windows Service Control Manager.
Outcome:
The Commander Service Portal should resume normal operations with improved performance and no

The Commander Service Portal should resume normal operations with improved performance and no
503 Service Unavailable errors.- Start the Commander service from the Windows Service Control Manager.
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