Update: We’ve extended the deprecation deadline to February 2, 2015 to give Pages users more time to update their DNS records.

If you use a custom domain with GitHub Pages, please verify that your domain’s DNS settings are properly configured to point to the most up-to-date GitHub IP addresses. This will ensure that your site remains available after December 1st, 2014.

GitHub Pages allows you to set up a custom domain by adding the domain to a CNAME file, and pointing your domain’s DNS record to GitHub’s servers. If you don’t use this feature, for example, if your GitHub Pages site is published as username.github.io, you don’t need to take any action at this time. Please enjoy this animated GIF for being awesome.

Why the change?

Nearly a year ago, we announced improvements to how we serve GitHub Pages sites. Today we’re making that change permanent by deprecating our old GitHub Pages infrastructure. If your custom domain is pointed at these legacy IPs, you’ll need to update your DNS configuration immediately to keep things running smoothly.

How long do I have to make the switch?

Starting the week of November 10th, pushing to a misconfigured site will result in a build error and you will receive an email stating that your site’s DNS is misconfigured. Your site will remain available to the public, but changes to your site will not be published until the DNS misconfiguration is resolved.

For the week of November 17th, there will be a week-long brownout for improperly configured GitHub Pages sites. If your site is pointed to a legacy IP address, you will receive a warning message that week, in place of your site’s content. Normal operation will resume at the conclusion of the brownout.

Starting December 1st, custom domains pointed to the deprecated IP addresses will no longer be served via GitHub Pages. No repository or Git data will be affected by the change.

How do I know if I’m affected?

If you have a GitHub Pages site pointed at one of the old IP addresses, you will receive an email from us this week letting you know that you need to make the change (and should have been receiving an email on each push for the past several months). If the suspense is killing you, there’s a few ways to check yourself:

  1. If you’re using the GitHub Pages Gem, update to the latest version, and run github-pages health-check from your site’s root directory. That’ll make sure your site’s DNS is in ship-shape.
  2. Don’t have the GitHub Pages Gem?
    • If you’re on a Mac or Linux machine, simply paste this command into a terminal window, replacing your-domain.com with, your site’s domain. dig your-domain.com | grep -E '(207.97.227.245|204.232.175.78|199.27.73.133)' || echo "OK". If you see the word “OK”, you’re all set.
    • On a Windows machine, you’ll want to run nslookup your-domain.com and ensure that the output does not include any of the deprecated IP addresses (207.97.227.XXX, 204.232.175.XX, or 199.27.73.XXX).
  3. From your domain registrar’s web interface, head on over to your domain’s DNS settings. Your domain should either be a CNAME record to username.github.io, an ALIAS record, or an A record pointing to an IP address that begins 192.30.252.XXX.

Okay, I’m sold. What do I need to do?

If one of the methods above indicate that your DNS is misconfigured, or if you just want to be sure, please follow the instructions for setting up a custom domain with GitHub Pages.

Questions? We’re here to help.

Happy publishing!