Status code 502 Bad Gateway is an HTTP error response code indicating that a server acting as a gateway or proxy received an invalid response from an upstream server. This error occurs when there is a communication issue between servers in the network chain, rather than a problem with the client’s request.
How It Works
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Client Request: The client sends a request to the gateway/proxy server.
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Gateway Processing: The gateway/proxy server attempts to fulfill the request by forwarding it to an upstream server.
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Communication Error: The gateway receives an invalid or incomplete response from the upstream server.
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Error Response: The gateway returns a 502 Bad Gateway error to the client to indicate the communication failure.
 
What to Do When Encountering in a Browser
- Refresh the Page:
 
- First, try refreshing the page as the error might be temporary
 - Wait a few minutes before trying again if the error persists
 
- User Troubleshooting:
 
- Clear browser cache and cookies
 - Try accessing the site from a different browser
 - Check if the website is down for other users using online tools
 - Test your internet connection with other websites
 
- Advanced Troubleshooting (for administrators):
 
- Check the upstream server’s health and connectivity
 - Verify server configurations
 - Monitor server logs for specific error details
 - Check network connectivity between gateway and upstream servers
 - Ensure adequate resources on both servers
 
Overall, status code 502 Bad Gateway indicates a server-side communication problem. While users can try basic troubleshooting steps, resolving the issue typically requires action from the system administrators or service providers managing the affected servers.