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Mr__T's avatar
Mr__T
Icon for Cirrus rankCirrus
Feb 23, 2023

Irule Vs rewrite - FQDN hostname

Hi All, New to IRules, and rewrites.  Clients will type appname.domain.com, I need to redirect to another URL (working via IRule) that the server understands but keep the friendly name appname.doma...
application delivery
Paulius's avatar
Paulius
Icon for MVP rankMVP
Mar 13, 2023

Mr__T If your pools have multiple pool members I do not believe this will be possible because you will require mapping a single FQDN to multiple server names depending on the pool member that you are sent to. Your best bet here would be to work with the server/app admins to see if they have a way of changing what they expect for the host and path. Typically all of this can be done at the server level instead of performing a bandaid at the F5 which in some cases such as yours will not work because of the single FQDN to many names issue.

Mr__T's avatar
Mr__T
Icon for Cirrus rankCirrus
Mar 13, 2023

Only 1 server in the pool. We tried to get the app owners to correct this at the application but they could not.

So the server is expecting https//:servername:8443/etc/ etc/etc/landingpage. Cosmetically, the app owner does not want to see unfriendly name. 

 

  • Paulius's avatar
    Paulius
    Icon for MVP rankMVP
    Mar 13, 2023

    Mr__T The following is the base iRule and you can continue to add on additional "elseif" to this to account for additional applications and change the port "8080" to the respective port.

    when HTTP_REQUEST priority 500 {

    if {[string tolower [HTTP::host]] == "example.com"} {
        HTTP::host [string map {"example.com" "servername.example.com:8080"}[HTTP::host]]
    }

}