Originally Posted by lpmusic
Sure CNAME's are nice if you have to change IPs, but why would you have to in the first place if this is in a datacenter (aside from a datacenter move which would probably have you worried about bigger problems).
Hey, all big problems start out as small problems. An ounce of prevention is worth a pound of cure.
1. DC customers do change IP's. Not often, quite rare, but it does happen.
2. Server failover to other locations outside of your DC, city, state or country.
3. IPv6 migration
4. Moves within a DC and between DC's.
5. If your IPs become blacklisted or something. Not due to yourself but someone in a neighboring subnet.
All in all using CNAMES whereever possible is always a good idea. It is less of a factor if:
1. You are an ISP and have your OWN IP space from ARIN.
2. You host and manage your own name servers.