referencing the VS default pool as destination in iRule

David,

How about something like this:

when CLIENT_ACCEPTED {
     Save the name of the VS default pool
    set default_pool [LB::server pool]
}
when HTTP_REQUEST {
  switch [string tolower [HTTP::host]] {    
    "www.domain-a.de" -
    "www.domain-b.de" -
    "www.domain-c.de" { 
        send these to default pool
       pool $default_pool 
       }
    default { HTTP::redirect "https://[HTTP::host][HTTP::uri]" }
  }
}

I've not got my lab bigip available to can't test but hopefully it'll do the job you require.

N