Google Message Security Troubleshooting Guide - Manual (Page 32)

Frequently Asked Questions 33
MX Records and IP Addresses
What are the IP addresses for the email security service?
The following are the IP ranges for the email security service. Note, for system 20
customers, both sets of IP ranges are applicable.
For information on how to find your system number, see IP Range.
What are DNS MX records?
When your domain is registered, it is assigned several DNS records, which enable
it to be located on the Internet. These include MX records, which direct the
domain’s mail flow. Each MX record points to an email server that is configured to
process mail for that domain. There is typically one record that points to a primary
server, then additional records that point to one or more backup servers. For
users to send and receive email, their domain's MX records must point to a server
that can process their mail.
To filter messages through the email security service, you must insert new records
that instead point to the service’s servers.
For more information, see the Activation Step-by-Step Guide’s How MX Records
Work FAQ.
How do I find the DNS information in the Administration
Console?
The DNS instructions can be found in your organization’s settings page. For
additional information, see Changing MX Records for a Domain.
What is the correct syntax for updating my MX records?
The exact steps and syntax vary depending upon the domain host you use. For
more information, see “What’s the format of a MX record?” question in the
Activation Step-by-Step Guide’s How MX Records Work FAQ.
System IP Range CIDR Range IP/Subnet Mask Pair
5, 6, 7, 8, 20 64.18.0.0 -
64.18.15.255 64.18.0.0/20 64.18.0.0
mask 255.255.240.0
20, 200, 201 207.126.144.0 -
207.126.159.255 207.126.144.0/
20 207.126.144.0
mask 255.255.240.0