The site for people they like to build Network Servers with CentOS, Ubuntu, Fedora, Debian, Windows Server.
PeeringDB is a freely available, user-maintained, database of networks, and the go-to location for interconnection data. The database facilitates the global interconnection of networks at Internet Exchange Points (IXPs), data centers, and other interconnection facilities, and is the first stop in making interconnection decisions.
This calculator returns a variety of information regarding Internet Protocol version 4 (IPv4) and IPv6 subnets including possible network addresses, usable host ranges, subnet mask, and IP class, among others.
NetworkLessons.com offers a range of Networking courses, including Cisco CCNA, CCNP and CCIE Routing & Switching. You find an overview of all courses below.