Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

Forum Discussion

ngkin2010's avatar
ngkin2010
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Apr 14, 2020

Effect of Rewriting HTTP Response

Hi mates,   I have write a simple F5 iRule to rewrite the HTTP response on LTM.   The code is simple: when HTTP_RESPONSE { if [HTTP::header "Content-Length"] > 50000000 { HTTP:...
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Simon_Blakely's avatar
Simon_Blakely
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Apr 15, 2020

First up, you don't need to do anything with the HTTP response if you are doing an HTTP::respond

 

The HTTP::respond 503 is complete in and of itself, and discards the collected HTTP response

 

The client-side connection just stays open for the next HTTP request from the client.

If you want to close the connection, use HTTP::close

 

ngkin2010's avatar
ngkin2010
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Apr 15, 2020

Hi Simon,

 

Thanks for you explanation and advise.

 

However, if the response will be discarded, and server-side connection stay open. Will the client-side connection also stay open? Will it cause TCP re-transmission if the HTTP response be discarded?

 

And I not quite familiar with HTTP::collect, and not sure I need it to determine the correct Content-Length. As I am expecting the first Content-Length in the first HTTP response is referring to the whole static content size even the content is spitted into multiple packets?

 

Again, thanks a lot Simon :)