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Wes_98712's avatar
Wes_98712
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Nov 08, 2011

Header Inserts

I am experiencing a somewhat odd situation. I created an HTTP profile and setup a name value pair in the Request Header Insert (SSL_ENV:On). When I debug in Fiddler to see if the header is inserted, I...
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Wes_98712's avatar
Wes_98712
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Nov 09, 2011
Another update, after a lot of testing we discovered something odd about the way F5 is inserting the header value

If we use an iRule (HTTP::header insert SSL_ENV On) or if we set the Request Header Insert in the http profile (SSL_ENV: On) either way F5 can see the header and reports that the value is set to On, but the server can't see the value: 

if Request.ServerVariables("HTTP_SSL_ENV")="On" then
response.write("WES Pass: " & Request.ServerVariables("HTTP_SSL_ENV") & "
")
else
   response.write("WES Fail: " & Request.ServerVariables("HTTP_SSL_ENV:") & "
")
end if

The output is always Wes Fail: (kind of ironic). But the ltm logs show the following if I capture the header value in the ltm log: 

when HTTP_REQUEST {
   if { [HTTP::header "HTTP_SSL_ENV"] equals "On" } {
      log local0. "HEADER HTTPS is: [HTTP::header "HTTP_SSL_ENV"]"
   }
}

Results:

Nov 9 15:29:36 tmm info tmm[7845]: Rule /Common/test_irule : HEADER HTTPS is: On

Nov 9 15:30:06 tmm info tmm[7845]: Rule /Common/test_irule : HEADER HTTPS is: On

Nov 9 15:30:46 tmm info tmm[7845]: Rule /Common/test_irule : HEADER HTTPS is: On

Nov 9 15:30:46 tmm info tmm[7845]: Rule /Common/test_irule : HEADER HTTPS is: On

Nov 9 15:31:38 tmm info tmm[7845]: Rule /Common/test_irule : HEADER HTTPS is: On

Nov 9 15:31:38 tmm info tmm[7845]: Rule /Common/test_irule : HEADER HTTPS is: On

So now I'm kind of stuck wondering why ASP can't read the value in the header using the ServerRequest function, but yet in RAW output or ALL_HTTP it can. Do I need to do something different with the header insert on the F5?