relay-test-1.peerlify.net is a relay server operated by Peerlify.
Peerlify connects the devices of a person or an organization into a private network. Devices talk to each other directly whenever they can. When a direct path is blocked, for example by NAT or a firewall, they exchange their traffic through a relay such as this one. That traffic is end-to-end encrypted between the devices, so the relay forwards data it cannot read.
Peerlify apps connect to this host automatically. It serves no other content.
More about Peerlify and its network requirements: https://peerlify.com.