On Thu, 4 Nov 1999, Bob Nielsen wrote: > > Yes, you can point A records from two domains to the same IP address. > > You can also use a CNAME record. I'm not sure when one approach would > be preferred over the other.
The answer is simple: Use A records for everything and forget about CNAMEs. :} I use a CNAME when a machine is supposed to have multiple names for the same purpose. For example, if your machine is "www.foo.com" and you also want it to be "www.department.foo.com" then use a CNAME. But if your machine is "mail.foo.com" and you also want it to be "mail.bar.com" then use an A record, because foo.com and bar.com are not the same entity. Another way to look at it is to use CNAME for aliases to a machine. For example, if your organization mandates stupid names for machines like "tor-fde1" and you want the machine to also have a name that people can remember, then you could also call the machine "teddybear" and use a CNAME for that. Then, if tor-fde1 changes IP addresses, teddybear goes with it.