Bug ID 899097: Existence of rewrite profile with HTTP profile response chunking mode 'sustain' always triggers client-side chunking

Last Modified: Sep 13, 2023

Affected Product(s):
BIG-IP Install/Upgrade, LTM(all modules)

Known Affected Versions:
15.0.0, 15.0.1,,,,,,,,, 15.1.1, 15.1.2,, 15.1.3,, 15.1.4,, 15.1.5,, 15.1.6,, 15.1.7, 15.1.8,,, 15.1.9,, 15.1.10

Opened: Apr 15, 2020

Severity: 3-Major


When using the rewrite profile, unchunked server responses where content-type is not text/HTML or text/CSS also gets converted to chunked encoding in client-side. Also, the server response is missing a message-body (no content-type/content-length). The client device receives 'Transfer-Encoding: chunked' in the message-header and receives a chunked body if the origin response has a message-body. The client receives a zero-length chunk if the origin response has no message-body. Prior to BIG-IP version 15, chunking happens only if origin server response has content-type header set to either text/HTML or text/CSS.


End users may notice a change in chunking behavior after upgrading from prior release.


- HTTP profile response chunking is set to 'sustain'. - The virtual server has rewrite profile attached. - Server response has content-type not set to text/HTML or text/CSS or no content-type header.


Use response chunking mode 'unchunk'.

Fix Information


Behavior Change

Guides & references

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