The Windows Server 2019 Essentials Edition is designed for small business with up to 25 users and 50 devices. Licensing is socket based and it allows only one instance of the Windows Server to run in the physical or virtual environment. User and Device Client Licenses are not required nor available.
The Windows Server 2019 Standard Edition is ideal for physical or minimally virtualized environments. It is great, cost effective option for small-to-medium-sized business with flexibility to go-as-you-grow with additional virtual licenses available at the time of purchases or after. Processor-core based licensing continue and 16 core base license include 2 virtual machines. The basic license allows two instances of Windows Server Standard in a virtual environment on a licensed server with one instance running on a bare metal. The bare metal instance, when used with 2 instances in VM, can be used for server management only. Additional Standard licenses are available for purchase.
The Windows Server 2019 Datacenter Edition is ideal for highly virtualized datacenters and cloud environments and corporations of all sizes. It allows users to run an unlimited number of Windows Server instances on a server, in physical and virtual environments, including containers. It includes all the features of the Standard edition plus support for encrypted virtual machines, software-defined networking, and software-defined storage. Licensing remains processor-core based with minimum of 16 core licenses per server and minimum 8-core licenses per processor.
Ubuntu is a free and open source operating system and Linux distribution based on Debian. Ubuntu is offered in three official editions: Ubuntu Desktop for personal computers, Ubuntu Server for servers and the cloud, and Ubuntu Core for Internet of things devices. New releases of Ubuntu occur every six months, while long-term support releases occur every two years. Support subscriptions for Ubuntu can be purchased for 1 year, 3 years and 5 years.
Red Hat® Enterprise Linux® (RHEL) is an open source operating system designed for edge of network and core data center workloads. RHEL is a subscription-based operating system licensed in 2- and 4-socket versions. Within each socket licensing is an additional licensing option to choose one virtual image, four virtual images or unlimited virtual images to run on top. RHEL can be used in small, medium and large corporate and government organizations without additional licensing and comes in 1, 3- and 5-year subscriptions.
SUSE® Linux Enterprise Server (SLES) is an open source operating system designed to handle workloads running in large data center environments down to single-server environments. SLES is a subscription-based operating system that allows you access to patches, fixes and security updates through their customer portal. SLES subscriptions can be used on 1, 2- and 4-socket servers and can be purchased in 1 year, 3-year and 5 year subscriptions..