Unknown MX records. Help!

Question

I am using the spf record creator at http://www.openspf.org/ and it's telling me we have 14 mx records. This is not right. We use google apps for our email and when I check our host records it is only showing the google mail servers. When I use the spf record generator it states the information below.

    This wizard found 14 names for the MX servers for mydomain.com:
    `enter code here` alt1.aspmx.l.google.com, gy-in-f27.1e100.net, 
    aspmx5.googlemail.com, bw-in-f27.1e100.net, yi-in-f27.1e100.net, 
    qy-in-f27.1e100.net, aspmx2.googlemail.com, aspmx.l.google.com, 
    pv-in-f27.1e100.net, aspmx3.googlemail.com, aspmx4.googlemail.com,
    ww-in-f27.1e100.net, ew-in-f27.1e100.net, and alt2.aspmx.l.google.com. 
    (A single machine may go by more than one hostname. All of them are shown.) 
    MX servers receive mail for mydomain.com. 
    Do they also send mail from mydomain.com?

Where are these other mx records coming from? Is there a way I can block them?

Answer 1

http://www.pcmech.com/article/the-mysterious-1e100-net/

What is 1e100.net? It’s Google. A WHOIS lookup for that domain reveals it’s owned by them.

Why would Google use an "weird" domain name like 1e100.net? It’s symbolic of a googol (10×10^100) which is where Google gets its name from.

Answer 2

This isn't a major problem.

That tool is first looking up your MX records. That's all those Google.com domains you see there. That tool is then also listing alternate DNS records for those IP addresses, determined via a reverse-DNS lookup. So you're also seeing the 1e100.net FQDN for each Google MX record for your domain. So those 7 records turn into 14. Nothing to worry about.

As Ceejayoz has shown, 1e100.net is just a different domain for Google's Content Delivery Network.

--Christopher Karel