Lab 2.4: Troubleshooting 503 Service Unavailable

Note

Estimated time to complete: 5 minutes

Lab environment access

If you have not yet visited the page Getting Started, please do so.

Tasks

1. Login as paula in BIG-IQ.
2. Select the application service security_site16_boston located under airport_security application.
3. Let’s generate additional traffic to the application security_site16_boston, connect on the Ubuntu Lamp Server and launch the following command:

# /home/f5/f5-demo-app-troubleshooting/503.sh

4. Back to BIG-IQ Application dashboard, security_site16_boston and display the Transaction Analytics.

• Click Expand the right-edge of the analytics panel to get the filters.
• Move the URLs and the Response Codes tables next to each other and expand them both (the tables can be moved up/down).
• In the Response Codes table, select the 200 and 503 lines.
• Click right on the Response Codes and click on Add Comparison Chart.

5. Finally, only select the 503 error in the filters and notice the page f5_capacity_issue.php shows up.

It appears from the data showing on BIG-IQ the application may start having issue (error 503) when more traffic is going through it.

Using the data available in BIG-IQ Application dashboard, we can narrow down 503 error and troubleshoot the inability of an application to handle production data capacities.