How often do Fastly's IP ranges change?


#1

We’re setting up a firewall whitelist for Fastly’s IP ranges. We plan to use the IP-whitelist-cron shell script to track the IP range changes, but our network admin would like to know if there is any frequency to these changes.


#2

Roughly 2-3 times per year, so far.


#3

Thank you, @drwilco. As a quick follow up, are IP changes announced before they are implemented?


#4

Yes. First the API endpoint is updated, then we post an update on status.fastly.com, and finally after a little grace period we start using the new IP space.

The status page has an RSS feed, which also alerts you of maintenance and any network outages, so it’s a good idea to put the feed somewhere you will see its updates. A lot of our customers add the feed to their ops channel on Slack, for instance.


#5

@drwilco about how long is that grace period? I assume since the example script only runs once a week, it would be well over a week, right?


#6

It has generally been multiple months, or even up to a year, in the past, but it’s a good idea to try to act within a couple of weeks. So once a week like the script does should suffice indeed.