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b31_133250's avatar
Icon for Nimbostratus rankNimbostratus
Jan 19, 2018

How can I preserve the original HTTP Host Header to the Backendservers?

Hi guys,


I'm trying the following configuration to loadbalance a RH SSO Key cloack Cluster:


clientIP -> https/443 -> (clientssl-Profile) F5-Virtual Server (serverssl-Profile) -> SNAT-IP -> tcp8443 -> Backendserver


The Backendserver need to see the original client http Header, so I created a http Profile with the "Insert X-Forwarded-For"-Option enabled.


Alternative I tried the following iRule:


when HTTP_REQUEST { HTTP::header insert X-Forwarded-For [IP::client_addr] }


Unfortunaly, both ways didn't work properly... How can I preserve the whole original HTTP Host Header trough the F5 to the Backendservers?


Thank you!


3 Replies

  • This is the default behavior. X-Forwarded-For option insert client IP address in headers, but doesn't change the Host header.


  • F5 does not change HTTP headers by default. You can add headers (e.g. X-FORWARDED-FOR) thru http profile config. You can add/delete/modify host headers thru iRule.


  • Surgeon's avatar
    Ret. Employee

    by default big-ip does not modify http headers. what does make you think that headers are being modified?