Shared Server Allocation

Perhaps someone can clear up some confusion I and someone else have had. I noticed that when I host a new domain, or add hosting to a sub-domain, that when I view the DNS entries, I see different IP addresses. Are these truly different physical shared servers that the domains/sub-domains are being hosted on, or does a single account have all their domains/sub-domains located on the same physical host? Do the different IPs mean different physical hosts or are these servers multi-homed for SSL or other reasons?

It was my (perhaps) naive thought that new domains/sub-domains are allocated in something of a round robin method or somehow the new domains are added to the server with the lowest load, but I’m open to being entirely wrong on this.

If it’s the same User (not account), it’d be the same machine. You can get your machine list here:

So user is the primary login to Dreamhost control panel? Or is that Account? I guess my question then becomes: what is is that a single server or a cluster or something else?

On shared hosting the machine itself will have many IP addresses. refers to the hostname of the shared server itself. When you add hosting to a domain, it’s added to 1 of several shared apache instances running on the shared server. Each of those apache instances has it’s own IP address. In the end, although all of your sites may be running on the same shared server bifur, they may be assigned to different apache instances, and thus different IP addresses.

To clarify, there is the primary dreamhost account (who pays for the plan, and such) and then there are usernames that are tied to each hosting instance. Is there a mechanism by which usernames are distributed amongst servers? I have 4 different usernames, but they all are on bifur it seems. Is it “just chance” that all 4 usernames are located on bifur?

I wouldn’t bet my life on it, but odds are that all users on your account will be on the same physical machine. I don’t know the DreamHost mechanism for adding users. All I can guarantee is that all domains under one user will be on the same physical machine.

Okay, that seems like a fair and good enough analysis…Thanks.