HTTP troubleshooting
304 Not Modified
Your uptime monitor detected that the server did not send the web page data because the page has not changed since the last time it was checked. The server tells the monitor to reuse its downloaded copy to save internet data and speed up loading times.
What 304 Status Code Means
- 1.
Cached content check
The server checks special tags sent by the monitor to see if the website content is exactly the same as the stored version.
- 2.
Bandwidth saving
The server sends a tiny message instead of the whole web page to save network data for both sides.
- 3.
Uptime monitor behavior
Our monitor checks these security and cache tags to make sure the server is healthy and alive, even if no new page data is sent.
Troubleshooting checklist
- 1.
Check cache headers
Look at the server response headers like ETag or Last-Modified to ensure they are being generated correctly.
- 2.
Verify request tags
Make sure the monitor or browser is sending the If-None-Match or If-Modified-Since tags properly.
- 3.
Test with a hard refresh
Try opening the page while forcing the browser to ignore its saved copy to see if the server still works normally.
- 4.
Review CDN settings
Check if your content delivery network (CDN) or caching plugin is stuck and serving old status data.
How to Fix It
- 1.
Clear cache systems
Purge your website caching plugins, reverse proxies, or CDN storage if you want to force the server to send new data.
- 2.
Update page content
Make a small change or edit to the website page to force the server to update its modification time stamp.
- 3.
Fix header configuration
Correct any broken rules in your server setup files that might be sending wrong caching instructions.
- 4.
Adjust monitor settings
Ensure your uptime monitor rules accept a 304 code as a successful check since the server is responding correctly.
After the Service is Fixed
- 1.
Verify with Uptime Monitor
Confirm that the monitor shows a healthy green status now that the server and caching rules are working together.
- 2.
Check live updates
Open your website normally to ensure that new updates and changes show up for regular visitors immediately.
- 3.
Track server loads
Watch your server performance metrics to see if saving data with these codes helps lower your CPU use.
- 4.
Audit header changes
Keep a record of your caching rules so future updates do not accidentally stop visitors from seeing new content.