We have a server running Plesk 7.5.3 handling the hosting and mail duties for many domains. Until now, we have been using all of the domains primarily resting on a single IP address (virtual hosting), with a few extra IP addresses configured for temporary use. I am wondering what other people do in regards to allocating IP addresses to hosting clients. Our upstream provider says they will allocate as many IP addresses as we need, but up until now we have only used a minimal amount. Do other people here typically assign a new IP address per hosted domain, assuming they have the IP addresses available from their providers? The reasons for asking this are my attempts to move towards providing proper reverse dns functionality for all of my hosted domains. I am hoping to cut down on the occasional email messages "lost in delivery" that we occasionally experience. Up until now we have not properly configured reverse DNS, but in the process of doing so, I am wondering whether we should just go all the way and assign each new hosted domain an IP, thus simplifying the work when configuring the reverse DNS (since each IP will map to that single hosted domain). We currently provide our existing virtualhosting services, where many domains are living on the one IP address. During my reading about reverse DNS, the articles I have read typically frown upon providing multiple PTR records for the same IP address because they are dished out randomly to requesting lookups. Any advice or past experience on this would be helpful. I would be happy to provide more information if needed.