Slow speed on client devices with a Linewize Filter Appliance inline

This article discusses some troubleshooting steps to follow if you have a Linewize Filter Appliance installed at your school and notice that client devices have slow networking connectivity issues. Please attempt each of the troubleshooting steps before contacting Linewize Support.

Step 1: Collect debug logs

Attempt to collect debug logs for Linewize Support while the issue is occurring, this will help Linewize Support diagnose the issue.

1. Access the Linewize Filter Appliance CLI either via SSH.
2. Run the command system debug collect while the issue is occurring.
3. Logs will be automatically uploaded to Linewize Filter. Proceed to Step 2.
4.  

Step 2: Temporarily turn off filtering

Try temporarily turning off filtering to see if it improves the network speed.

1. In Linewize Filter, select the three vertical dots next to your device's name.
2. Select Turn Off Filtering Temporarily.
3. At the confirmation message, select Turn Off Filtering. 
4. Wait a few minutes to see if the network speed has improved.
   

   Note

   You don’t need to enable filtering; it will automatically re-enable filtering after five minutes.

   • If this hasn’t resolved your issue, proceed to Step 3.

Step 3: Change DEFAULT_VERDICT_DENY configuration

1. Go to Debugging > Diagnostics > Advanced Configuration.
2. Look for DEFAULT_VERDICT_DENY
3. Set to False.
4. Select Save.
5. Wait a few minutes to see if the network speed has improved.
   • If this hasn’t resolved your issue, proceed to Step 4.

Step 4: Change APP_FILTER_HANDLER__FILTER_ENABLED configuration

1. Go to Debugging > Diagnostics > Advanced Configuration.
2. Look for APP_FILTER_HANDLER__FILTER_ENABLED
3. Set to False.
4. Select Save.
5. Wait a few minutes to see if the network speed has improved.
   • If this hasn’t resolved your issue, change it back to True and proceed to Step 5.
   • If this resolves your issue, one or more of your filtering policies are causing the issue with the appliance. The next step would be to check which filter policies are causing the issue. The quickest way to do this would be to turn off filter policies one at a time and see which policy is causing the issue.

Step 5: Change other Advanced Configurations

1. Go to Debugging > Diagnostics > Advanced Configuration.
2. Try turning off each advanced configuration settings one by one. Before moving on to the next configuration, ensure you test on client devices for a few minutes:
   1. APPL_HANDLER__HTTPS_ENABLED
   2. APPL_HANDLER__HTTP_ENABLED
   3. APPL_HANDLER__DNS_ENABLED
   4. APPL_HANDLER__HTTPPROXY_ENABLED
   5. APPL_HANDLER__QUIC_ENABLED_2
   6. APPL_HANDLER__HTTPS_DIRECTIP_FILTERING_ENABLED
   7. APP_FILTER_HANDLER__SAFESEARCH_ENABLED
   8. APP_FILTER_HANDLER__MOBILEZONE_POLLING_HANDLER
   9. APP_FILTER_HANDLER__CAPTIVEPORTAL_ENABLED
   10. APP_FILTER_HANDLER__LOGOUT_HELPER_ENABLED
   11. APP_FILTER_HANDLER__MOBILEZONE_USER_ACCESS_HANDLER_2
   12. APP_FILTER_HANDLER__CHROME_EXTENSION_ENABLED
       • If this hasn’t resolved your issue, re-enable all the settings, then proceed to Step 6.

Step 6: Contact Linewize Support

If you have completed all the troubleshooting steps here and still have speed issues, contact Linewize Support with your findings for more help.

Troubleshooting Checklist