Rewrite Rule triggers the 502 server Error


I am currently using the load balancer and LiteSpeed on the Google Cloud Platform (GCP).

The problem is whenever I rewrite rules as shown below on the Litespeed admin panel, it triggers the 502 server error.

RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$$1 [R,L]
However, another rewrite rules as shown below works.

RewriteCond %{HTTP_HOST} ^12\.34\.56\.78 [OR]
RewriteCond %{HTTP_HOST} ^www.example\.com$
RewriteRule ^(.*)$$1 [R,L]
Based on my research, the 502 error occurs whenever the server TCP session timeout (Keep-Alive timeout) is shorter than the default TCP session timeout of the GCP, which has 600 secs.

I understand that I can modify the Keep-Alive timeout in the LightSpeed's admin panel, but only up to 60 secs.

To fix the issue,

1) how can I adjust the Keep-Alive timeout more than 60 secs?

If my presumption is wrong,

2) Is there any other reason or solution to solve the 502 server error?

Addition: When I applied Rewrite Rules suddenly 404 Page error occurred. Deleting and Re-updating a same rewrite rule solved the issue.

Thank you
Last edited:



Even if you don't apply rewrite rules, keep-alive is still enabled by default on OLS, so your presumption might be wrong.
About 404, please remove the GCP Load Balancer and check if the issue still reproducible.

thank you for your reply.
This is not my presumption. It is officially listed in Google cloud doc.

And I have confirmed with Google that Keep alive timeout will trigger the server drop from Load Balancer if the Keep alive timeout of the server is less than 600 secs