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Forum Discussion

daveclarkjr's avatar
daveclarkjr
Icon for Nimbostratus rankNimbostratus
Nov 11, 2016

host replace question with iRule

Is there any way to keep F5VSserver.null.com as the host? Would using HTTP::host be an option?   client request   https://f5VSserver.null.com/?uri=http://Server1.null.com/xyz/go?app_url=http:...
application delivery
BIG-IP
iRules
Vernon_97235's avatar
Vernon_97235
Historic F5 Account
Nov 11, 2016

I'm not 100% sure I understand the question, but breaking down the original client request:

https://f5VSserver.null.com/?uri=http://Server1.null.com/xyz/go?app_url=http://Server2.null.com:8000/http_handler/file.htm

would create an HTTP Request message that looks something like this:

GET /?uri=http://Server1.null.com/xyz/go?app_url=http://Server2.null.com:8000/http_handler/file.htm HTTP/1.1
Host: f5VSserver.null.com
... other headers here ...

Unless you use a Local Traffic Policy or iRule to modify the Host header, it will remain unchanged as the HTTP Request message is proxied to the selected Pool Member. The only thing your rule is modifying is the Request Target (aka, the Request URI) which is the field immediately after the GET method in the start-line. The requested hostname is not part of the Request Target.