@AngeloF I presume it is actually an MX105 you are referring to?  As mentioned above you cannot have more than one active MX in a network and the passive has to be the same model as the active.  However you can have more than one MX in a site, just create a second network.   For all of our sites we have at least three MXs and divide them into multiple networks to suit our needs.   What are you trying to achieve? ... View more