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Karlsen_58024's avatar
Karlsen_58024
Icon for Nimbostratus rankNimbostratus
Nov 28, 2012

HTTP Redirection iRules

Hi,

 

A customer wanted a new web solution and chose Big-IP 3900 to use as a load balancer. They want to migrate from the existing environment to the new one with as little downtime / 404 errors as possible by redirecting old links to the corresponding site in the new environment.

 

This has led me to create a ton of redirection rules. I am pretty new to Big-IP, so I would like to know what the best practices are around handelig a lot of URIs. This is how I solved it:

 

 

 

when HTTP_REQUEST {

 

if { ([string tolower [HTTP::host]] contains "example.com") and [HTTP::uri] contains "/thisisanoldsite" } {

 

HTTP::redirect "https://www.example.com/this/is/the/equivilant/site"

 

}

 

if { ([string tolower [HTTP::host]] contains "example.com") and [HTTP::uri] contains "/hey/whatsup.aspx" } {

 

HTTP::redirect "https://www.example.com/abc/def/example.aspx"

 

}

 

if { ([string tolower [HTTP::host]] contains "example.com") and [HTTP::uri] contains "/page206.aspx" } {

 

HTTP::redirect "https://www.example.com/subsite/URI/page.aspx"

 

}

 

if { ([string tolower [HTTP::host]] contains "example.com") and [HTTP::uri] contains "/AboutThisPage" } {

 

HTTP::redirect "https://www.example.com/About/Page.aspx"

 

}

 

...

 

}

 

}

 

This rule is applied on the HTTP Virtual Server. As you can see, everything is redirected to https://, so this iRule will only be applicable on the users first request.

 

 

This is just a small part of it. The complete rule contains about 1200 URIs, devided in two seperate iRules.

 

 

 

Can this be changed into something a little less complex? Using switch insted of if's? I would also like if these rules replied with a HTTP 301 Permanently moved status code. Should I replace every HTTP::redirect with HTTP::respond 301 location ?

 

 

In advance, thank you.

 

 

Regards,

 

Martin

 

application delivery
dev
devops
iRules

4 Replies

  • nitass's avatar
    nitass
    Icon for Employee rankEmployee
    Nov 28, 2012
    what about this one? 

    [root@ve11a:Active:Changes Pending] config  tmsh list ltm virtual bar
ltm virtual bar {
    destination 172.28.19.252:443
    ip-protocol tcp
    mask 255.255.255.255
    profiles {
        clientssl {
            context clientside
        }
        http { }
        tcp { }
    }
    rules {
        myrule
    }
    snat automap
    vlans-disabled
}
[root@ve11a:Active:Changes Pending] config  tmsh list ltm data-group internal redirection_class
ltm data-group internal redirection_class {
    records {
        /AboutThisPage {
            data /About/Page.aspx
        }
        /hey/whatsup.aspx {
            data /abc/def/example.aspx
        }
        /page206.aspx {
            data /subsite/URI/page.aspx
        }
        /thisisanoldsite {
            data /this/is/the/equivilant/site
        }
    }
    type string
}
[root@ve11a:Active:Changes Pending] config  tmsh list ltm rule myrule
ltm rule myrule {
    when HTTP_REQUEST {
   if { [string tolower [HTTP::host]] equals "example.com" } {
      if { [class match -- [HTTP::uri] equals redirection_class] } {
         HTTP::respond 301 noserver Location "https://www.example.com[class match -value [HTTP::uri] equals redirection_class]" Connection Close
      }
   }
}
}

[root@ve11a:Active:Changes Pending] config  curl -Ik https://example.com/AboutThisPage
HTTP/1.0 301 Moved Permanently
Location: https://www.example.com/About/Page.aspx
Connection: close
Content-Length: 0
  • Brian_Deitch_11's avatar
    Brian_Deitch_11
    Historic F5 Account
    Nov 28, 2012
    If you are not a fan of multiple IF statements or data groups you could do nested switches: 

    


when HTTP_REQUEST {
   switch -glob [ string tolower [HTTP::host]] {
     *example.com* { 
        switch -glob [ string tolower [HTTP::uri]] {
          *thisisanoldsite* { HTTP::redirect "https://www.example.com/this/is/the/equivilant/site" }
          */hey/whatsup.aspx* { HTTP::redirect "https://www.example.com/abc/def/example.aspx" }
          */page206.aspx* {  HTTP::redirect "https://www.example.com/subsite/URI/page.aspx" }
          */aboutthispage* {  HTTP::redirect "https://www.example.com/About/Page.aspx"  }
           default { HTTP::respond 301 noserver Location "https://www.example.com" }
        }   
      }   
     *nextdomain.com* {
        switch -glob [ string tolower [HTTP::uri]] {
          *thisisanoldsite* { HTTP::redirect "https://www.nextdomain.com/this/is/the/equivilant/site" }
          */hey/whatsup.aspx* { HTTP::redirect "https://www.nextdomain.com/abc/def/nextdomain.aspx" }
          */page206.aspx* {  HTTP::redirect "https://www.nextdomain.com/subsite/URI/page.aspx" }
          */aboutthispage* {  HTTP::redirect "https://www.nextdomain.com/About/Page.aspx" }
           default { HTTP::respond 301 noserver Location "https://www.nextdomain.com" }
       }   
    }   
  }   
}