URL hostname rewrite

Sure can. If you just want to change the host header sent to your backend server while maintaing the support.mycompany.com to your end users, just use the HTTP::header command to change the host header. Something like this should work

when HTTP_REQUEST {
  if { [HTTP::host] eq "support.mycompany.com" } {
    HTTP::header replace "Host" "server1.mycompany.com"
  }
}

The "if" check on the host is only in case you are multi-hosting this iRule. If you want to unconditionally change the host value sent back to the server, you can just use the HTTP::header replace command by itself.

Keep in mind though that if you pass a host value to the back end app server, that some app servers may generate page links based on the passed in host header. If your app did this, you'd have to have a DNS entry for server1.mycompany.com that goes to your VIP.

If you want to do a redirect (which is not what it sounds like you want, you can do a simple redirect

when HTTP_REQUEST {
  if { [HTTP::host] eq "support.mycompany.com" } {
    HTTP::redirect "http://server1.mycompany.com[HTTP::uri]"
  }
}

Hope this helps...

-Joe

You should just need to change the Host header in the request. Example:

when HTTP_REQUEST {
    HTTP::header replace Host "server1.mycompany.com"
}

Guys, this is great thanks for the quick reply!!

 

In this case we have 8 servers in the pool so how can I create the iRule so it works depending on the specific pool member?

 

Two options:

1. You could maintain a data group that maps the name to the IP. Example:

   datagroup (ex. my_server_dg):
   
   10.10.42.10 := server1.domain.com
   10.10.42.11 := server2.domain.com
   10.10.42.12 := server3.domain.com
   
   iRule:
   when HTTP_REQUEST_SEND {
       clientside {
           HTTP::header replace "Host" [class match -value [LB::server addr] equals my_server_dg]
       }
   }
   

2. If you have internal DNS you could do a quick reverse lookup to get the name.