irule to select pool based on fqdn

You can use a if statement:

when HTTP_REQUEST {
  if { [HTTP::host] eq "web1.xyz.com" } {
    pool poolA
  } elseif { [HTTP::host] eq "web2.xyz.com" } {
    pool poolB
  }
}

or with a switch statement:

 when HTTP_REQUEST {
  switch [HTTP::host] {
    "web1.xyz.com" { 
      pool poolA
    }
    "web2.xyz.com" {
      pool poolB
    }
  }
}

I've been told that switch statements are let CPU intensive but it's really probably a toss in this situation. Use which ever method is easier for you to follow

-Joe

We have something very similar to this. Is it possible to have two different FQDN point to the same VIP and have them select pools based on FQDN?

 

 

Example:

 

https://uat.site1.com/blah1

 

https://uat.site1.com/blah2

 

Resolves to 10.0.1.25

 

 

and

 

 

https://conv.site1.com/blah1

 

https://conv.site1.com/blah2

 

Resolves to 10.0.1.25

 

 

Could we parse the header and send them to a particular pool? We would need preserve the URI. The only other thing I can think of is we do a http to https:// redirector via an iRule.

 

 

Thanks to anyone that replies!

 

 

Regards -

 

 

/ja

The fqdn will be stored in the HTTP::host value. Here's how you could do it with a switch statement. An if/elseif would work just as well.

when HTTP_REQUEST {
  switch [HTTP::host] {
    uat.site1.com {
      pool pool_a
    }
    conv.site1.com {
      pool pool_b
    }
    default {
      log local0. "Uknown site: [HTTP::host]"
    }
  }
}

-Joe

If we have the following iRule currently applied to the VIP, how will this play into what we are wanting to do?

 

 

when HTTP_REQUEST {

 

HTTP::redirect https://[getfield [HTTP::host] ":" 1][HTTP::uri]

 

}

 

 

thanks and best regards -

 

 

/ja

If you are doing a redirect to an HTTPS virtual, then assigning a pool doesn't make much sense in this rule. I would apply the redirect iRule to the HTTP virtual and apply the host matching iRule to the HTTPS virtual.

 

 

-Joe

Good point. We will apply the iRule in our lab to test and see how the application works with the pool selection. Thanks so much for your time!

 

 

Regards -

 

 

/ja

I have but one last question that was passed on by one of my co-workers. Will this preserve the URI? I ask because behind each URL is two applications. The trailing URI /blah1 and /blah2 point to two different applications. The way our devs. have Appache configured as best I understand, is to parse the HTTP request for the URI (/blah1 or /blah2) to determine which application pool to send the request to.

 

 

So the end goal is to have one VIP point to two pools. Have the iRule parse the host header (preserving the URI if possible) and send it to the appropriate pool.

 

 

For UAT Site -

 

https://uat.site1.com/blah1 (/blah1 goes to application 1)

 

https://uat.site1.com/blah2 (/blah2 goes to application 2)

 

Resolves to 10.0.1.25

 

 

and

 

 

For Conversion Site -

 

https://conv.site1.com/blah1 (/blah1 goes to application 1)

 

https://conv.site1.com/blah2 (/blah2 goes to application 2)

 

Resolves to 10.0.1.25

 

Using the pool command to assign a pool to the current connection will not effect any of the protocol specific data. The host headers, URI, POST data, and everything else will remain the same. This just instructs our load balancing engine which pool of servers to choose from.

 

 

-Joe

Can you select a pool based on what comes after the fqdn? For instance

 

 

For UAT Site -

 

https://uat.site1.com/blah1 (/blah1 goes to application 1)

 

https://uat.site1.com/blah2 (/blah2 goes to application 2)

 

https://uat.site1.com/blah3 (/blah2 goes to application 3)

 

 

where /blah1 goes to application 1 which is in pool 1

 

and /blah2 goes to application 2 which is in pool 2

 

and /blah3 goes to application 3 which is in pool 3

 

and so on?

 

 

 

 

Hi Shawn,

 

 

I replied to your post here:

 

https://devcentral.f5.com/Community/GroupDetails/tabid/1082223/aft/2163314/asg/50/Default.aspx

 

 

Aaron