Hi all, I'm not sure if this is the most appropriated list to submit my question but however it might be a security issue. OK, here it goes: we have 3 boxes in the same netmask, broadcasting 62 public IP address. One (mine) is running SuSE 7.2, and I'm hosting 16 domain names. I've 2 network cards and a couple of virtual net address. I realised that if I use any of those IP's to another machine (it happened by mistake.), I lose internet access in my Linux box, and the domain is unreachable. Kinda normal(?), but it could be dangerous if someone hack into one of the Win boxes and start changing IP's.that won't be problem if there is a way to block giving the same IP to 2 machines (just like the Win boxes do when you try to give them an IP already used in the same netmask). Otherwise, it can be considered as an important security hole, am I wrong? The thing is I just don't know how fix that. Thanks, M.Albuquerque