iRule redirection to different port

You'll need to modify the log to output the URI that is captured in the else condition. Once a match is made in an 'if' statement it breaks out and stops processing further conditions so the 'else' should not be matched if it was previously matched in the preceding 'if'

when HTTP_REQUEST {
  if { [HTTP::uri] starts_with "/xyz" } {
    log local0. "If condition matched with URI:[HTTP::uri]"
    Pool abc_pool
  } else {
    log local0. "else condition matched with URI:[HTTP::uri]"
    pool Default_pool
  }