iRule to tack on full domain

Which LTM version are you running? You could create a string type datagroup with the UQDNs and FQDNs on a line together. For v9.x, you can use the findclass command (Click here). For v10.x, you could use the new class command (Click here) or findclass to parse the datagroup and look up the requested hostname and get the corresponding FQDN.

Here is an example using a datagroup and the findclass command:

 
  Datagroup (aka class in the bigip.conf) 
  Make sure to use lower case for the entries 
 class uqdn_to_fqdn_mapping { 
    "host1 host1.example.com" 
    "host2 host2.sub.example.com" 
    "host3 host3.another.example.com" 
 } 
 

 
 when HTTP_REQUEST { 
     
     Comment out or remove the logging once done testing 
    log local0. "[IP::client_addr]:[TCP::client_port]: New [HTTP::method] request to [HTTP::host][HTTP::uri]" 
  
     Check if requested host header does not contain at least one period 
     This will also avoid trying to redirect requests to IP addresses 
    if { not ([HTTP::host] contains ".")}{ 
  
      log local0. "[IP::client_addr]:[TCP::client_port]: Host did not contain a period." 
  
        Look up the requested host in the datagroup 
       set fqdn [findclass [string tolower [HTTP::host]] $::uqdn_to_fqdn_mapping] 
       log local0. "[IP::client_addr]:[TCP::client_port]: Match? $fqdn" 
  
        If there was a match, send a 301 redirect to the client, preserving the URI 
       if {$fqdn ne ""}{ 
          log local0. "[IP::client_addr]:[TCP::client_port]: Redirecting client to https://$fqdn[HTTP::uri]" 
          HTTP::respond 301 Location "https://$fqdn[HTTP::uri]" 
       } 
    } 
 } 
 

Note, if you're on 9.4.4 or higher, remove the $:: from the name of the datagroup reference in the iRule (set fqdn [findclass [string tolower [HTTP::host]] uqdn_to_fqdn_mapping]).

Aaron