On Wed, Nov 30, 2011 at 2:59 AM, Fajar Priyanto <fajarpri at arinet.org> wrote: > Hi all, > I have plan to replace my Centos5.7 VM with newer version. > The VM works as our network gateway. > > I want to ask from your experience, will it be a bad decision? My > concern is that since the Mac Address of the gateway will change, will > it disrupt the network? > How fast the Switches can recognize the new mac? Any other pitfall? Switches normally flood all ports until a new mac is identified so they will work as soon as the link comes up (which may take a few seconds for spanning tree). However, routers to adjacent subnets may cache their arp table for up to 20 minutes. You might have a problem with inbound connections if you don't clear the arp table on whatever is connected as the next hop. -- Les Mikesell lesmikesell at gmail.com