All HTTP versions

By default Unified Origin server will try to use HTTP/2 for "https://" and HTTP 1.1 for "http://", but you can force Unified Origin to use specific version of HTTP by using subdomains:

HTTP 1.1

When you use http11.vm-ean-0.nl-ams.linode.unified-origin.com subdomain for connection, traffic will be served using HTTP 1.1 for both "http://" and "https://".

HTTP/2

When using http2.vm-ean-0.nl-ams.linode.unified-origin.com subdomain, server will use HTTP/2. It will not work for "http://" (which needs to be enabled for Let's Encrypt verification).

HTTP/3

If your client supports HTTP/3 / QUIC virtual host, then http3.vm-ean-0.nl-ams.linode.unified-origin.com and quic.vm-ean-0.nl-ams.linode.unified-origin.com subdomains are configured to advertise support for it through "Alt-Svc" header. This is also only available for "https://" communication. When you are using Chrome, it is very strict about used QUIC version, so if you see that Chrome is not switching to h3 most probably you need to upgrade used OLS version (using /opt/upgrade_ols.sh script).