Today we will be gradually rolling out a version update of Varnish and Nginx on the Xenial Hypernodes.
Nginx will be upgraded from nginx/1.10.2 to nginx/1.13.1. The changelog for the differences between these versions can be found here. Our current 1.10.2 build has IPv6 disabled, which we expected to be fine since the Hypernodes do not have IPv6 enabled at this point in time.
However, it turned out that a lot of people use configuration snippets that do assume Nginx IPv6 compatibility (even though the server does not support it and those rules would be mostly void) which would invalidate the config. There is one exception though, and that is when CloudFlare or a similar service proxies IPv6 traffic transparently to the webserver. For those reasons we’ve re-enabled IPv6 support in Nginx in this version.
Additionally, Varnish will be upgraded from varnish-4.1.1 to varnish-4.1.3. This update addresses some incompatibility issues with the magento-turpentine plugin for Magento 1.