Redirect to Multiple URLs

This should work for you.

when RULE_INIT {
  set ::whichone 0
}
when HTTP_REQUEST {
  switch $::whichone {
    0 {
      HTTP::redirect "http://Server1/blah"
    }
    1 { 
      HTTP::redirect "http://Server2/blah" 
    }
  }
  set ::whichone [expr ! $::whichone]
}

Basically it's setting a global variable and toggles it between 0 and 1 on each http request. Then, depending on the current value it issues the appropriate redirect.

Or, you could do the same without the expr command and using a default case to avoid a second comparison on the value 1.

when RULE_INIT {
  set ::whichone 0
}
when HTTP_REQUEST {
  switch $::whichone {
    0 {
      HTTP::redirect "http://Server1/blah"
      set ::whichone 1
    }
    default { 
      HTTP::redirect "http://Server2/blah" 
      set ::whichone 0
    }
  }
}

Hope this helps...

-Joe

Joe - Thanks for the quick response. We are gettign ready to throw that in now. I'll let you know tomorrow if it worked.

 

-Darrin

Joe,

 

 

That worked great!!! Thank you for the assistance.

 

 

-Darrin

So I have another piece I was just asked to address with this. Is there a way to do a health check of the site I'm redirecting to prior to sending the client there? Something like....

 

 

when RULE_INIT {

 

set ::whichone 0

 

}

 

when HTTP_REQUEST {

 

switch $::whichone {

 

0 {

 

if healthcheck passes then

 

HTTP::redirect "http://Server1/blah"

 

else

 

HTTP::redirect "http://Server2/blah"

 

}

 

1 {

 

if healthcheck passes then

 

HTTP::redirect "http://Server2/blah"

 

else

 

HTTP::redirect "http://Server1/blah"

 

}

 

}

 

set ::whichone [expr ! $::whichone]

 

}

 

 

I'm not sure how to do a health check on a redirect site or if you can.

 

 

Thanks,

 

-Darrin

If you have that site defined as a pool member (you can add as a dummy host), then you can use the LB::status command as a conditional before redirecting. Here's the wiki page for the LB commands:

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/LB__status.html Click here

Can you have a redirect site as a pool member? How do you create a dummy host?

What Joe gave me above works perfectly, but I'd like to add one more piece to that. So I want the iRule to redirect to two different sites and technically load balance them which is what Joe's code does. But now I'm curious if, before it sends the user to the redirect site, can the iRule do a health check of that site and if it's down, send the user to the other redirect site.

Look three posts up the thread...

I can't define sample.domain.com/blah as a node or a pool member. I can do sample.domain.com. I'm trying to redirect to another site and a page on that site.

There isn't a good way that I can think of to do health-checks on remote sites. It's pretty easy to redirect users to wherever you want, but health-checking remote systems is a little more tricky.

 

 

Colin