Issue wih BIG-IP upgrade (12.1.2 to 14.0.0.4)

Question

Today, we upgraded a BIG-IP cluster (mode Active/Active) from version 12.1.2 to version 14.0.0.4. After the upgrade, almost all applications start to fail 
intermittently with an error ERR_INVALID_HTTP_RESPONSE. The problem ocurred ONLY in Chrome browser, and in Firefox, Opera and Edge everything worked fine. There is no error in LTM logs.  Someone has experienced this problem?&nbsp;

michael_saleem · Answer

I have not seen this issue. &nbsp;
However, I would start by checking your iRules. For example do you have a HTTP_RESPONSE event containing multiple re-directs for a single IF condition?&nbsp;

pedro_roure · Answer

After some research on the Internet we found that the error was possibily related with some null characters in HTTP reponse, more specifically in HTTP headers. So we did a packet capture and found out that the BIG-IP system was sending the following Set-Cookie header filled with nulls:&nbsp;
Set-Cookie: f5_cspm=1234\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;\000;
&nbsp;
Since this cookie is related to the AVR feature, we disabled the HTTP analytics on all virtual servers that had this enabled, to force the BIG-IP system stop to sending this Set-Cookie. After this, we tried the upgrade again and the upgrade worked perfectly and the error ERR_INVALID_HTTP_RESPONSE did not ocurred anymore on Chrome browsers.&nbsp;
As a second test (for confirmation), after the upgrade we enabled the HTTP analytics profile again in some virtual servers and the issue happened again: the applications start to fail in Chrome browsers with an error message of ERR_INVALID_HTTP_RESPONSE. &nbsp;
So, I think is a somekind of bug in the BIG-IP for this version. &nbsp;

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