Forum Discussion

onlineops's avatar
onlineops
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May 01, 2018

irule: root domain (only) non-www to www redirect

I have a series of websites that need a non-www to www redirect, bu I still need to support direct subdomains without a redirect.

Example:

  1. http://abc.com redirects to http://www.abc.com
  2. http://bank.abc.com does not redirect and stays at http://bank.abc.com

Assume:

  • I have a bunch of domains here and don't want write a conditional statement by domain, it's too brittle
  • I have several subdomains to support and would prefer not to conditionally address each, but can if necessary
  • I need to do http and https

A simple irule that handles 1, but not 2, http only:

    when HTTP_REQUEST {
  if { ! ([HTTP::host] starts_with "www.") } {
    HTTP::redirect http://www.[HTTP::host][HTTP::uri]
  }
}

What's an efficient way to say "redirect root domains only" ?

devops
iRules
LTM
  • OM's avatar
    OM
    Icon for Nimbostratus rankNimbostratus
    May 01, 2018

    Hi, fo a specific domain irule, you can use:

     

    when HTTP_REQUEST { if { ([HTTP::host] eq "abc.com")}{ HTTP::redirect .[HTTP::host][HTTP::uri] } }

     

    For global domain irule, you might need a regex, maybe something like this:

     

    when HTTP_REQUEST { if { ([HTTP::host] eq "^[^.]+$.com") } { HTTP::redirect .[HTTP::host][HTTP::uri] } }

     

  • onlineops's avatar
    onlineops
    Icon for Nimbostratus rankNimbostratus
    May 02, 2018

    That rule will work for the TLD (Top Level Domains) .com - and again, if I don't want to get specific about doing "OR" for all the possible TLDs, I think this works, regardless of top level domain:

    when HTTP_REQUEST {
  if { ([HTTP::host] matches_regex {^[a-zA-Z0-9]+\.[a-zA-Z]{2,4}$}) } { HTTP::redirect http://www.[HTTP::host][HTTP::uri] } 
}


when HTTP_REQUEST {
  if { ([HTTP::host] matches_regex {^[a-zA-Z0-9]+\.[a-zA-Z]{2,4}$}) } { HTTP::redirect https://www.[HTTP::host][HTTP::uri] } 
}