On May 15, 2008, at 7:34 PM, Clint Dilks wrote:
I am currently reviewing the DNS records for the organization I work for and have one area I would like other peoples thoughts on. Would there ever be a situation where you need to have multiple A records pointing to the same IP Address?
Currently we have a small number of cases where one IP Address has multiple A Records. This seems like a bad idea to me and I would replace these records with cnames. But I am meeting resistance to this. As far as I can think right now if you have one correctly configured A record with a matching reverse entry and then use cnames there shouldn't be any cases where you must add a second A record. Or am I missing something ?
A shared web server is a good example of multiple As resolving to the same IP.
CNAMEs require two dips into the DNS (one to get the CNAME, another to look up the IP), and so can be much slower if you are the victim of a slow resolver.
--Chris