Bug ID 852917: Accept-Encoding header is removed when websso form-based is used

Last Modified: Apr 18, 2022

Bug Tracker

Affected Product:  See more info
BIG-IP APM(all modules)

Known Affected Versions:
14.1.0,,,,,, 14.1.2,,,,,,,,, 14.1.3,, 14.1.4,,,,,,, 15.0.0, 15.0.1,,,,, 15.1.0,,,,,, 15.1.1, 15.1.2,, 15.1.3,, 15.1.4,, 15.1.5,

Fixed In:

Opened: Nov 25, 2019
Severity: 3-Major


Service published behind LTM-APM virtual server type, with forms-based single sign-on showing ??? characters for non-English languages.


The Accept-Encoding header may be removed.


-- Form-based single sign-on (SSO) is configured for a virtual server. -- Non-English characters exist.


Add the following iRule: when HTTP_REQUEST_RELEASE { if { [HTTP::header exists "Accept-Encoding"] } { HTTP::header replace "Accept-Encoding" "gzip, deflate" } else { HTTP::header insert "Accept-Encoding" "gzip, deflate" } }

Fix Information

Accept-Encoding header is removed only when the log level for SSO is set to Debug. Accept-Encoding remains untouched for all other log levels.

Behavior Change