Bug ID 1624557: HTTP/2 with RAM cache enabled could cause BIG-IP to return HTTP 304 with content

Last Modified: Dec 05, 2024

Affected Product(s):
BIG-IP LTM(all modules)

Known Affected Versions:
17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3, 17.1.1.4, 17.1.2

Opened: Aug 07, 2024

Severity: 3-Major

Symptoms

When the server replies to BIG-IP with HTTP 304 (not modified) and the BIG-IP system returns the contents of the RAM cache, it will not change the HTTP code 304 returned by the server when sending the cached content back to the client. The client will reject the HTTP 304 with content since it is expecting 200 OK with content.

Impact

The BIG-IP system sends the response to the client as a 304 along with the content, causing the client to reject the content.

Conditions

-- Content in RAM cache has expired -- The BIG-IP system requests an update from the origin server -- The origin server returns 304 Not Modified.

Workaround

Disable RAM cache or alternatively have the server never return HTTP 304 but rather the content with 200 OK, even if unchanged.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips