CNAME records to simplify mail management

Question

This is my first post so sorry for any generic formatting that I might be missing.

I'm trying to reduce the amount of configuration changes that our client would need to perform when we move their website around our servers. We plan to host the clients email with Google Apps and I was wondering if this would be a valid scenario to set up DNS to support a different mail provider if we decide to switch from Google to something else.

Basically what I have in mind:

I'd create two CNAME records (the example.com domain is my clients domain here):
pop.example.com -> pop.gmail.com
smtp.example.com -> smtp.gmail.com

and then the required MX records that Google provides would also be created for example.com.

Would this setup cover such scenario that when we want to switch server we only update the DNS and the client does not need any configuration changes on their side? (obviously we still need to keep using pop3 and smpt to keep it compatible but I'm only asking about the DNS changes here)

Thanks for any help

Answer 1

You will be fine with the cname records for the pop and imap but if you change from Google down the line you still might have to reconfigure client email programs because Google requires:

Incoming server must be 993, and must use SSL encryption. Outgoing server can use 587, TLS encryption.

It's also a good idea to add spf records and domain keys to avoid your clients emails getting tagged as spam from Yahoo or MSN

If your server uses PHP to send mail for any applications of course you will need to include the hostname and ip address to your spf.

SPF Records:

example.com 14400 in TXT "v=spf1 include:aspmx.googlemail.com ~all"

example.com 14400 in TXT "v=spf1 a mx ip4:xxx.xxx.xx.xxx include:aspmx.googlemail.com ?all"

Answer 2

These are for the client email program, correct? If so, that should be ok as long as you don't use CNAME records for the actual MX records.

Answer 3

You could CNAME them, but it will cause the SSL certificates to go mad.