Lots of specific URLs to 301 redirect - best approach?

Paul,

Yes, a data group and short iRule would be perfect for this.

Create a string data group, for the purposes of this example, called datagroup_redirects. The String would be the url you want to match on and the Value would be the url you want to redirect to. So the entries would look something like...

www.domain.com/if/this/is/requested := http://www.domain.com/redirect/to/here

The code to perform the redirect would be something like...

when HTTP_REQUEST {
    if { [class lookup [HTTP::host][HTTP::uri] datagroup_redirects] ne "" } {
        HTTP::respond 301 Location [class lookup [HTTP::host][HTTP::uri] [datagroup_redirects]
    }
}

Attach the iRule to the appropriate Virtual Server.