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Thanks Aaron for your reply : I am checking different examples but as I'm really new to irules I was just hoping someone used to irules would have an example to get me started because I'm having some troubles with the syntax at the time being :-) I'm not even able to test the command on the BIG-IP, I'm just giving a model of what we expect which doesn't make things easy for me. So if anybody has an example nearby, that would be great!