What is a ttl setting – Google Message Security Troubleshooting Guide User Manual
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And for detailed examples of the more common domain hosts, see .
Why is the priority of MX records important, anyway?
Inserting the new MX records at a higher priority than your existing records directs
mail flow to email security servers where it can get filtered, instead of sending it
directly to your mail server where no filtering occurs.
An MX record consists of three parts: the domain name, a priority, and an email
host. The priority indicates which record gets looked at first when determining
where to route a message sent to the domain. Normally, the primary server
named in the record with the highest priority, is used. But if that server is not
available, the next highest priority’s record is evaluated, which is typically a
backup server. And so on.
For more information, see “What’s the format of a MX record?” question in the
Activation Step-by-Step Guide’sFAQ.
What if my domain’s MX records are not prioritized using a 1
through 4 numbering scheme?
Priority is often indicated using the numbers 100-600, where 100 has the highest
priority. But if your DNS service prioritizes them differently, for example using a 1-
6 numbering scheme, or a 10-60 numbering scheme, that is OK, too. You can use
any scheme, as long as the new entries are inserted at a higher priority than any
existing entries. When inserting the email security service MX records, we
recommend using a number scheme of 1 through 4.
For more information, seequestion in
the Activation Step-by-Step Guide’s How MX Records Work” FAQ.
What is a TTL setting?
When you change a domain’s MX records to point at a different server, the
change does not take effect immediately. Instead, it has to propagate throughout
the Internet. How long this takes can depend on the current TTL, or Time to Live
setting. This is typically measured in seconds, so a TTL of 3600, for example,
means it might take up to an hour for the changed to propagate. Shortening the
TTL can make the change propagate more quickly. For more FAQ information,
see the “About MX Record Propagation” information.
For more information, see “What’s the format of a MX record?” question in the
Activation Step-by-Step Guide’s FAQ.