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NetWare
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The rise of NetWare
The popular use and growth of Novell NetWare began in 1985 with the simultaneous release of NetWare 286 2.0a and the Intel 80286 16-bit processor. The 80286 CPU featured a new 16-bit protected mode that provided access to up to 16 MB RAM as well as new mechanisms to aid multi-tasking. (Prior to the 80286, PC CPU servers used the Intel 8086/8088 8/16-bit processors, which were limited to an address space of 1MB with not more than 640 KB of directly addressable RAM.)
The combination of a higher 16 MB RAM limit, 80286 processor feature utilization, and 256 MB NetWare volume size limit (compared to the 32 MB that MS-DOS allowed at that time) allowed the building of reliable, cost-effective server-based local area networks for the first time. The 16 MB RAM limit was especially important, since it made enough RAM available for disk caching to significantly improve performance. This became the key to Novell's performance while also allowing larger networks to be built.
In another significant innovation, NetWare 286 was hardware-independent, unlike competing server systems from 3Com. Novell servers could be assembled using any brand system with an Intel 80286 or higher CPU, any MFM, RLL, ESDI, or SCSI hard drive and any 8- or 16-bit network adapter for which NetWare drivers were available.
Novell also designed a compact and simple DOS-client software program that allowed DOS stations to connect to a server and access the shared-server hard drive. While the NetWare server file system introduced a new, proprietary file-system design, it looked like a standard DOS volume to the workstation, ensuring compatibility with all existing DOS programs.
Early years
NetWare originated from consulting work by SuperSet Software, a group founded by the friends Drew Major, Dale Neibaur, Kyle Powell and later Mark Hurst. This work stemmed from their classwork at Brigham Young University in Provo, Utah, starting in October 1981.
In 1983, Raymond Noorda engaged[clarification needed] the work by the SuperSet team. The team was originally assigned to create a CP/M disk sharing system to help network the CP/M hardware that Novell sold at the time. The team was privately convinced that CP/M was a doomed platform and instead came up with a successful file-sharing system for the newly introduced IBM-compatible PC. They also wrote an application called Snipes – a text-mode game – and used it to test the new network and demonstrate its capabilities. Snipes [aka 'NSnipes' for 'Network Snipes'] was the first network application ever written for a commercial personal computer, and it is recognized as one of the precursors of many popular multiplayer games such as Doom and Quake.[1]
This network operating system (NOS) was later called Novell NetWare. NetWare was based on the NetWare Core Protocol (NCP), which is a packet-based protocol that enables a client to send requests to and receive replies from a NetWare server. Initially NCP was directly tied to the IPX/SPX protocol, and NetWare communicated natively using only IPX/SPX.
The first product to bear the NetWare name was released in 1983. There were two distinct versions of NetWare at that time. One version was designed to run on the Intel 8086 processor and another on the Motorola processor which was called NetWare 68 (aka S-Net); it ran on the Motorola 68000 processor on a proprietary Novell-built file server and used a star network topology. This was soon joined by NetWare 86 V4.x, which was written for the Intel 8086. This was replaced in 1985 with Advanced NetWare 86 version 1.0a which allowed more than one server on the same network. In 1986, after the Intel 80286 processor became available, Novell released Advanced NetWare 286 V1.0a and subsequently V2.0B (that used IPX routing to allow up to 4 network cards in a server). In 1989, with the Intel 80386 available, Novell released NetWare 386. Later Novell consolidated the numbering of their NetWare releases, with NetWare 386 becoming NetWare 3.x.
NetWare 286 2.x
NetWare version 2 had a reputation as notoriously difficult to configure, since the operating system was provided as a set of compiled object modules that required configuration and linking. Compounding this inconvenience was that the process was designed to run from multiple diskettes, which was slow and unreliable. Any change to the operating system required a re-linking of the kernel and a reboot of the system, requiring at least 20 diskette swaps. An additional complication in early versions was that the installation contained a proprietary low-level format program for MFM hard drives, which was run automatically before the software could be loaded, called COMPSURF.
NetWare was administered using text-based utilities such as SYSCON. The file system used by NetWare 2 was NetWare File System 286, or NWFS 286, supporting volumes of up to 256 MB. NetWare 286 recognized 80286 protected mode, extending NetWare's support of RAM from 1 MB to the full 16 MB addressable by the 80286. A minimum of 2 MB was required to start up the operating system; any additional RAM was used for FAT, DET and file caching. Since 16-bit protected mode was implemented the i80286 and every subsequent Intel x86 processor, NetWare 286 version 2.x would run on any 80286 or later compatible processor.
NetWare 2 implemented a number of features inspired by mainframe and minicomputer systems that were not available in other operating systems of the day. The System Fault Tolerance (SFT) features included standard read-after-write verification (SFT-I) with on-the-fly bad block re-mapping (at the time, disks did not have that feature built in) and software RAID1 (disk mirroring, SFT-II). The Transaction Tracking System (TTS) optionally protected files against incomplete updates. For single files, this required only a file attribute to be set. Transactions over multiple files and controlled roll-backs were possible by programming to the TTS API.
NetWare 286 2.x supported two modes of operation: dedicated and non-dedicated. In dedicated mode, the server used DOS only as a boot loader to execute the operating system file net$os.exe. All memory was allocated to NetWare; no DOS ran on the server. For non-dedicated operation, DOS 3.3 or higher would remain in memory, and the processor would time-slice between the DOS and NetWare programs, allowing the server computer to be used simultaneously as a network file-server and as a user workstation. All extended memory (RAM above 1 MB) was allocated to NetWare, so DOS was limited to only 640kB; expanded memory managers that used the MMU of 80386 and higher processors, such as EMM386, would not work either, because NetWare 286 had control of protected mode and the upper RAM, both of which were required for DOS to use this approach to expanded memory; 8086-style expanded memory on dedicated plug-in cards was possible however. Time slicing was accomplished using the keyboard interrupt. This feature required strict compliance with the IBM PC design model, otherwise performance was affected. Non-dedicated NetWare was popular on small networks, although it was more susceptible to lockups due to DOS program problems. In some implementations, users would experience significant network slowdown when someone was using the console as a workstation. NetWare 386 3.x and later supported only dedicated operation.
Server licensing on early versions of NetWare 286 was accomplished by using a key card. The key card was designed for an 8-bit ISA bus, and had a serial number encoded on a ROM chip. The serial number had to match the serial number of the NetWare software running on the server. To broaden the hardware base, particularly to machines using the IBM MCA bus, later versions of NetWare 2.x did not require the key card; serialised license floppy disks were used in place of the key cards.
NetWare 3.x
Starting with NetWare 3.x, support for 32-bit protected mode was added, eliminating the 16 MB memory limit of NetWare 286. This allowed larger hard drives to be supported, since NetWare 3.x cached (copied) the entire file allocation table (FAT) and directory entry table (DET) into memory for improved performance.