NetWare® was the most popular network operating system (NOS) for servers and personal computers (PCs) during much of the 1980s and 1990s. Originally created by Novell, Inc. in 1983, it is a very high-performance client-server platform. Unlike Microsoft Windows® and UNIX®-based operating systems, NetWare® is not a timeshared interactive system. It is often used on servers to provide very efficient file, print and database services for many clients simultaneously. It is also used as a platform for high-availability clustering systems.
The first release of NetWare® was for the Motorola Incorporated 68000 processor using proprietary software on a Novell file server. Most, if not all, other versions are designed for Intel® Corporation processors in the x86 family. The next two releases were for the Intel® 8086 used in International Business Machines Corporation (IBM®) compatible computers.
Novell released NetWare® 286 to take full advantage of the new Intel® 80286 processor in 1986. It utilized the full 16 megabyte (MB) Protected Mode memory space for disk caching with an 80286-specific file system. It also included software Redundant Array of Independent Disks (RAID), system fault tolerance (SFT) and a transaction tracking and roll-back system. Up to four network cards could be used simultaneously as well. These features helped boost Novell's market share since many were only available on minicomputers and mainframes.
The Intel® 80386 version, NetWare® 386, utilized 32-bit Protected Mode and a much higher-capacity file system. A loadable module system replaced the prior release's cumbersome re-linking and re-booting requirement. The "non-dedicated" support for Microsoft®'s Disk Operating System (DOS) was also removed in this version. This had allowed a system to be used both as a network file server and a DOS-based user workstation. NetWare® 386 also included bindery and name services for authentication and distributing data across multiple servers.
Another 80386 version included a unique high-availability clustering solution called SFT-III. It was somewhat ahead of its time and split the NOS into event-driven and interrupt-driven portions. It also included support for multiple processors in the same machine. Using SFT-III a server could be mirrored to a separate machine across a very fast link.
Several more versions of NetWare® were released between 1993 and 2003, including a more advanced clustering system. Novell lost a serious amount of market share to Microsoft® during the same time, however. Novell's lack of support for Transmission Control Protocol (TCP) and Internet Protocol (IP) was one important reason. Users often preferred the graphical interface of Microsoft Windows® as well. Microsoft® also marketed its products to a much broader range of decision makers than Novell generally did.
Novell also included its kernel in versions of the Open Enterprise Server (OES) product. Originally released in 2005, OES is a set of core applications and services which can run on NetWare® or a Linux®-based server. In 2007, Version 2 of OES added virtualization and 64-bit processor support.