NetWare is a network operating system developed by Novell, which allows the networking of computers, be it DOS, Windows, Unix or Mac OS. NetWare had great success in the eighties as the first true network operating system compatible with standard IBM compatible PC and MS DOS.
The system required a dedicated server or semi-dedicated server, whose hard drive was formatted only for NetWare, and had its strength in software for clients, especially light, stable, and compatible with various platforms.
Among the many merits of NetWare is that of having introduced the concepts of large-scale information sharing and networking, which have become common for all modern companies and also have contributed to the spread of standard systems network that still survive, such as a card with Ethernet technology.
The NetWare system survives even today in many companies, although it has been replaced by the Open Enterprise Server (OES). The latest version of the NetWare 6.5 Support Pack 7 is identical to OES-NetWare Kernel Support Pack 2.
NetWare evolved from a very simple concept: sharing files rather than discs. In 1983, when he designed the first version of NetWare, all other competing products were based on the concept of providing direct access to shared disks. The alternative approach was approved by IBM to Novell in 1984 and this helped to promote the product.
With NetWare disk space was shared in the form of NetWare volumes, comparable to DOS volumes. Clients with MS-DOS would run a special program Terminate and Stay Resident (TSR) which allowed them to map a local drive letter to a NetWare volume.
The client had to authenticate to a server in order to get permission to map the volumes, and access could be restricted by user name. Similarly they could connect to shared printers on the dedicated server, and print as if the printer was connected locally.
NetWare captured a dominant market position in the first half of the nineties, developing its IPX / SPX, Xerox XNS junction and the standard local area network (LAN).
In the late nineties, with the boom in Internet connectivity, TCP / IP protocol became dominant on LANs. Novell had introduced limited support for the TCP / IP with versions 3.x (circa 1992) and 4.x (about 1995), consisting mainly of FTP services, printing services LPR / LPD UNIX-style (available with NetWare 3 . x), and a web server developed by Novell (in NetWare 4.x). Native support the TCP / IP for file and print services normally associated with Novell was introduced with NetWare 5.0 (released in 1998).
While some attribute the delay in the adoption of Novell’s TCP / IP as its native protocol to the loss of market share from NetWare, Novell can say that it was put out to let market. During the first half of the eighties, a system Microsoft introduced LAN with LAN Manager, based on the NetBEUI protocol.
The first attempts were unsuccessful fight with NetWare, but that changed with the inclusion of improved networking support in Windows for Workgroups, and then with the success of Windows NT and Windows 95. NT, in particular, offered services similar to those offered by NetWare, but on a system that could be used as a desktop, and connected directly to other Windows desktops where NetBEUI was almost universal.
The widespread use and growth of NetWare began in 1985 with the simultaneous release of NetWare 2.0a 286 processor Intel 80286 16-bit. The CPU 80286 CPU had a 16-bit protected mode which provided access to up to 16MB of RAM, multitasking efficient and reliable. Before dell’80286, servers with IBM PC architecture were based on Intel 8086/8088 of 8 bits, which were limited to 640K of RAM and were devoid of preemptive multitasking.
The combination of features dell’80286, limit to 16MB RAM and 256MB limit for the NetWare volumes, allowed for the first time to have server-based local economic networks. The limit of 16MB of RAM was of particular importance, since it made enough RAM available for disk caching, resulting in improved performance. This became the key to the performance of Novell and allowed the construction of larger networks.
Another important difference was that NetWare 286 was independent from the hardware, unlike competing server systems of 3Com. NetWare servers could be assembled using any system with 80286 CPU or higher, any hard disk MFM, RLL, SCSI or a network card to any 8 or 16 bits.
Novell also designed a simple and compact client software that allowed DOS station to connect to a server and access its shared disks. Although NetWare servers introduced a new file system owner, this seemed like a normal volume to the workstation DOS compatible, ensuring the functionality of all the existing DOS programs.
NetWare — The early years
NetWare was based on the work of the advisory SuperSet Software, a group founded by the friends Drew Major, Kyle Powell and Dale Neibauer, which later joined by Mark Hurst. This work was based on a project they began at Brigham Young University in Provo (Utah) as of October 1981.
In 1983 Raymond Noorda engaged the work of the team SuperSet. These were originally assigned to create a system of shared disks for CP / M, helping to network hardware, CP / M that Novell was selling at the time. In private, the team was convinced that CP / M was a doomed platform and instead came out with a successful file sharing system for newborn IBM PC-compatible.
The group also wrote an application called Snipes, a text-mode game that used to test the new network and demonstrate their capabilities. Snipes was the first network application ever written for a personal computer business, and is recognized as one of the forerunners of many popular multi-user games such as Doom and Quake.
This network operating system (NOS) was later called Novell NetWare. NetWare was based on the NetWare Core Protocol (NCP), which is a packet protocol that allows the client to send requests and receive replies from a NetWare server. Initially, the NCP was directly tied to the IPX / SPX, which meant they could only communicate using native NetWare IPX / SPX.
The first product to bear the name of NetWare was released in 1983. He was called Netware 68 (aka S-Net), turned on the Motorola 68000 processor and used a star network topology. He was replaced in 1985 by 86 NetWare version 1.5, which was written for the Intel 8086.
After the release of the Intel 80286, released in 1986, Novell NetWare 286. The same thing happened with the release of the Intel 80386, Novell released NetWare 386 in 1989. Following the consolidated version numbering Novell NetWare, NetWare 2.x which became 286, and 386 who became NetWare NetWare 3.x
286 NetWare 2.x
NetWare Version 2 was notoriously difficult to configure, since the operating system was supplied as a set of compiled object modules, which required to be configured and linked. Adding to this problem was the fact that this process was designed to run using multiple floppy disks, which made everything slow and unreliable.
Any changes to the operating system required a re-linking the kernel and a reboot of the system, for which they need at least 20 changes to disk. NetWare was administered using the text-mode utility such as SYSCON. The NetWare file system used by the NetWare File System 2 was 286, or 286 NWFS, which supports volumes up to 256 MB.
NetWare 2 recognized only dell’80286 protected mode, limiting its support to 16MB of RAM or less. A minimum of 2MB was required for booting the operating system, all the additional RAM was used for FAT, DET and file caching. Since the 16-bit protected mode dell’80286 was implemented on all processors after Intel’s x86 family, 286 NetWare version 2.x was able to run on any 80286 or later processor compatible.
NetWare 2 already implements several features inspired by mainframe and minicomputer systems that were not available on other operating systems at the time.
The features of System Fault Tolerance (SFT) included the standard test of reading after writing (SFT-I) with re-mapping on the fly for bad blocks (at the time the disc did not have this feature encoded in them) and the RAID1 software (disk mirroring, SFT-II). Optionally, the Transaction Tracking System (TTS) to protect the files from incomplete updates.
For individual files, it only requires the setting of an attribute of the file. Transactions on multiple files were checked and rollbacks can program the TTS API.
NetWare 2.x supports two modes of operation: dedicated and non-dedicated. In dedicated mode, the server used a boot loader that does the file net $ os.exe operating system. All the memory was allocated to NetWare, the server was not running DOS.
In a non-dedicated server was started on DOS 3.3 or higher, using a floppy disk or a bootable DOS partition on the hard disk. The DOS was limited to 640k, since you could not use any memory manager. Extended all the RAM was allocated to NetWare 2.x, and processor divided the processing time between DOS and NetWare.
The time slicing was achieved using the keyboard interrupt. This feature requires close adherence to the model of the IBM PC project, otherwise the performance was adversely affected. In small networks of 2 to 5 users, non-dedicated mode was very popular, although it was more susceptible to lockup problems due to DOS programs. NetWare 3.x and later versions support only the dedicated mode.
Continued : Novell Network – Part 2