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crazzyeddie
Jun 20, 2011, 09:10 AM
Hey guys,

I'm currently running two xServes, mainly for the purpose of hosting many websites. I want to transition these to virtual machines running Ubuntu Server on VMWare ESX for better security and uptime.

Does anyone know of any really good resources for figuring out how to set this all up? For instance, I would like to setup ISPConfig to allow for multiple sites per VM while still maintaining security, etc...

One of my more advanced problems/question is whether I can use a single IP address to host multiple sites, similar to virtual hosting, but on multiple VMs. I have read that this is referred to as Reverse DNS...

Any suggestions?



jtara
Jun 20, 2011, 11:24 AM
One of my more advanced problems/question is whether I can use a single IP address to host multiple sites, similar to virtual hosting, but on multiple VMs. I have read that this is referred to as Reverse DNS...

You can't have more than one VM with the same public IP address any more than you could have multiple real machines with the same public IP address. One address, one machine, real or virtual.

You'd have to set-up some sort of proxy or NAT arrangement in front of the VMs to pull this off. Of course, it will have to be sufficient powerful to handle all of the traffic.

But not sure why it would be important to you to have all of the sites on the same IP address?

Reverse DNS has nothing to do with this, and is simply the mapping of IP addresses back to domain names. It's important in some contexts (for example, email hosting) to have a reverse DNS entry. (Many mail agents will refuse to deliver to an IP address that doesn't have reverse DNS set-up.) It's a kind of "proof of ownership".

crazzyeddie
Jun 21, 2011, 07:09 AM
Perhaps my terminology is incorrect, but I understand what you're saying. I would have a proxy server handing requests off to the multiple sub-servers.

This does seem somewhat complex, but I've yet to find a simple solution to creating a situation with multiple virtual hosts that have chrooted ssh... suggestions on that?