SSHSSH
The way I use it is: I want all traffic going to our public website to be routed via the ASM module, our website is www.mycompany.com. Hence, I put *mycompany* as a Pattern String into the hosts list so any http request including this in the Host is matched and forwarded to the ASM. So Match Only hosts is a way of distinguishing which traffic is put through the ASM, according to the host part of the request.
In regards the "send to pool", we have it set at None, i.e. it uses the pool associated with the VS. But you could, with this setting, override this so it goes to a specific pool so all traffic that doesn't match the hosts list goes to the default pool, but ASM traffic goes to a different one.
Hope this helps.
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