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jerm1020_254086's avatar
jerm1020_254086
Icon for Nimbostratus rankNimbostratus
Aug 01, 2016

create a new Header value manipulation iRule

create a new Header value manipulation iRule. This iRule needs to interrogate Header values and substitute the x-forwarded-for value with True-Client-IP value if available. our CDN is providing the a...
application delivery
devops
iRules
LTM
xforward
Kai_Wilke's avatar
Kai_Wilke
Icon for MVP rankMVP
Aug 02, 2016

Hi Jerm,

you may use the iRule below to copy the 

"True-Client-IP"
header information (if present) into an additional 
"X-Forwarded-For"
header. If the 
"True-Client-IP"
header is not present, the iRule would simply store the client IP address of the underlying TCP session as 
"X-Forwarded-For"
header value...

when HTTP_REQUEST {
         Removing  existing "X-Forwarded-For" headers to avoid duplications.
        HTTP::header remove "X-Forwarded-For" 
         Check if "True-Client-IP" is present
        if { [set true_client_ip [HTTP::header value "True-Client-IP"]] ne "" } then {
             "True-Client-IP" header is present. Copying "True-Client-IP" value to "X-Forwarded-For"
            HTTP::header insert "X-Forwarded-For" $true_client_ip
        } else {
             "True-Client-IP" header is not present. Setting the real client IP as  "X-Forwarded-For"
            HTTP::header insert "X-Forwarded-For" [getfield [IP::client_addr] "%" 1]
        }
 }

Cheers, Kai