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Srinivasa_Chala's avatar
Srinivasa_Chala
Icon for Nimbostratus rankNimbostratus
Sep 17, 2018

Please assist me in creating irule

Hi All,

 

I need help in creating irule as i am new to F5. Please find the requirement details below.

 

Solution requirement : WebApplication running Hassle Free return application will make HTTPS API call to the F5 provided printer URL where : 1) F5 will provide HTTPs based DNS URL which will be mapped to multiple IP based printers located at corp. 2) Once received the request, F5 will terminate the HTTP connection at F5 and generate a HTTP call the printer hostnames ( or IP's). 3) F5 will use path based routing from request HTTPS URL to determine which specific printer this request need to be routed. 4) For a given URL like https://corpprinter.lsapps.net/{corpcode}/{printername}/ where {corpcode} and {printername} are dynamic elements, respective request will be routed to http://corpcode-printername.lsapps.net URL on F5.

 

Thanks!

 

application delivery
iRules
  • PeteWhite's avatar
    PeteWhite
    Icon for Employee rankEmployee
    Sep 17, 2018

    what do you mean by "respective request will be routed to"? Do you mean the requested will be redirected or that it will push it to a different virtual server or it will send it to a specific node in the pool?

     

  • Srinivasa_Chala's avatar
    Srinivasa_Chala
    Icon for Nimbostratus rankNimbostratus
    Sep 17, 2018

    Hi Pete,

     

    Thanks for your reply!

     

    Answer: It has to send it to a specific node.

     

    Thanks!

     

  • youssef1's avatar
    youssef1
    Icon for Cumulonimbus rankCumulonimbus
    Sep 17, 2018

    Hi,

    here is a good base to start. Once we reach our goal we can optimize the IRULE.

    So first of create a pool "pool-printer" with all your printer, suppose your printer listen on port 80:

    when HTTP_REQUEST {
  switch -glob [string tolower [HTTP::uri]] {
    "/corpcode1/printername1/" {
        HTTP::uri http://corpcode1-printername1.lsapps.net
        pool pool-printer member 10.10.10.1 80
    }
    "/corpcode2/printername2/" {
        HTTP::uri http://corpcode2-printername2.lsapps.net
        pool pool-printer member 10.10.10.2 80  
    }
    "/corpcode3/printername3/" {
        HTTP::uri http://corpcode3-printername3.lsapps.net
        pool pool-printer member 10.10.10.3 80  
    }
    default { 
         nothing 
    }
  }
}

    that's what I understood from your request if you see some things inconsistent, keep me update.

    regards,

  • Stanislas_Piro2's avatar
    Stanislas_Piro2
    Icon for Cumulonimbus rankCumulonimbus
    Sep 18, 2018

    Hi,

     

    you can use following code (not tested)

     

    It retrieve printer name, resolve printer address with DNS servers in pool p_dns, then define as

     

    when HTTP_REQUEST {
    if {[scan [HTTP::uri] {/%[^/]/%[^/]/} corpcode printername] == 2} {
        set printer "${corpcode}-${printername}.lsapps.net"
            HTTP::path [string map "/${corpcode}/${printername}/ /" [HTTP::path]]
            foreach dns [active_members -list p_dns] {   
             Check if the first list element was empty
            if {[set dest [lindex [RESOLV::lookup @[lindex $dns 0] -a $printer] 0]] ne ""} {
                 Set Node IP based on DNS resolution
                node $dest 80
                break
            }
        }
    }
}