New Features of NetWare 4.x

Jianping zeng Kelong wu

Index

Contents

• What is NetWare;

• Motivation for new NetWare 4.x features;

• NetWare Directory Service(NDS):

• Logical Organization of the network;

• Single Login to the network;

• Global Network Management;

• Independence from Physical Location of Resources;

• Improvements in the NetWare File System;

• Improved File System Security;

Index

Contents• Support for Network Auditing;

• Simplified and more efficient Memory Management Architecture;

• Improvements in Client Networking Services;

• Integrated Storage Management Services(SMS);

• Improvements in Network Print Service Architecture;

• Multiple Language Support;

• Simplified Installation and Upgrade Procedures;

• Conclusion.

Index

What is NetWare• Is an operating system for hosting file volumes

across a network --- a network operating

system(NOS);

• Was not designed as an application-development

platform, nor as a desktop operating system;

• Is one of the most well-established and strongest-

selling NOS product;

• Has more than half the file/print-sharing server

market, and might continue to hang on to that edge

into the next century.

IndexMotivation for NetWare 4.x• A network can consist of several LANs tied together with wide area links as shown in

figure 1

Figure1: NetWare-based network

Index

Motivation for NetWare 4.x

• The user would have to know the names of the file servers

to which the printer and volume resources are attached

before he access them;

• The user would have to log in to that server at first if he

wanted to use its resources;

• The user would have to attach to that server and then

create a separate drive mapping;

• Access to resources was controlled by a security

mechanism that was local to each other(called the bindery).

• In the earlier versions of NetWare

Index• In the NetWare 4.x

• It has the logical view of the network, resources are organized into groups that are in turn organized into a hierarchy that reflects their usage, function, or geographical location, and forget about the physical links(such as routers or bridges) shown as in figure 2;

• The user can login to this logical view of the network;

• Access to resources on the network can be controlled by security mechanisms that are global in scope and apply to entire network;

• To provide a single access to the network, NetWare 4.x created a global database called the NetWare Directory Service (NDS). NDS provide a global database service that is not confined to a single server and represents network-wide resources.

Index• In the NetWare 4.x

Figure 2: logical view of the network

Index

NetWare Directory Service (NDS)• Function of NDS:

It provides the network administrator and a logical view of a network;

The logical view of the network can be easily recognized by the user;

It provides a distributed database that can act as a repository of information on all the shared resources on the network;

Is replacement for the bindery services of the early version. The bindery could not easily support information on other nodes on the network.

Index

NetWare Directory Service (NDS)

• Benefits of NDS:

Logical organization of the network;

Single login to the network;

Global network management view;

Independence from physical location of resources.

IndexLogical Organization of the network

The resources can be grouped in a hierarchical in the NDS representation;

Make it easy for the users and network administrators to find the network resources without knowing the physical details of network connectivity;

The user who needs to use a network resource has a logical pointer (called object which contain information on the resource) to the NDS database;

In figure 3, a file server can be modeled as a file server object which contains the information such as the name of the file server, its network address, location, and so on.

Figure 3:file server object

Index

Single Login to the network

• Enables a user to be authenticated just once to access all the resources on the network even though he cannot access all the objects in this directory (figure 4);

• Administrator gives him the access priority;

Figure 4: single login

IndexSingle Login to the network

After a user logs in, the network administrator can limit access to resources on the network. When the user authentication is successful, the user is granted access to any resource on the network( figure 5);

Figure 5:user authentication to the network

Index

Single Login to the network

In earlier version, the user had to login every server to

which he wanted access and the number of such

concurrent connection was limited to 8;

In NetWare 4.x, the maximum number of concurrent

connections to different NetWare servers is increased

from 8 to 50.

Index

Global Network Management• In the early version, the network management tasks

had to be performed separately on each NetWare server, because network management usually resulted in a modification of the bindery, and the bindery was specific to each server;

In NetWare 4.x, the network administrator can change network resources from any place on the network. (figure 6);

Figure 6: global network management

IndexIndependence from Physical Location of Resources

• In the early version, the resources were described in a server bindery and depended on that server (figure 7);

• In NetWare 4.x, resources are not tied to a specific server or a physical location on the network. The NDS object can be accessed from any station on the network when the user gets the permission.

Figure 7: Bindery representations of printer definitions

Index

Improvements in the NetWare File System

• Block Suballocation Disk suballocation can be enable/disable at the

installation time;

The disk block size was selected at the

installation time to be 4KB, 8KB, 12KB, 16KB or

64KB;

NetWare 4.x allows small files and files that are

not multiples of the disk block size to share

space in a disk block that would otherwise have

gone wasted (figure 8).

Index

Improvements in the NetWare File System

Figure 8: Disk suballocation

Index

Improvements in the NetWare File System

• NetWare File System Compression

Compress option can be enable/disable at the

installation time (default is enable);

The disk block will be compressed as it is written

and decompressed by special decompress threads

as it is read (figure 9);

This compress option can increase the effective

disk space without adding new server drives.

Index

Improvements in the NetWare File System

Figure 9: Read of a compressed file

IndexImprovements in the NetWare File System

• Data Migration Allows infrequently used files to be moved to a

near-line storage medium (such as optical disk libraries) or off-line storage medium (such as tape backup devices);

When data migration occurs, NetWare 4.x still sees the data on the NetWare volumes;

If a file is accessed and it has been migrated, the file is brought back into the NetWare volume(figure 10);

It is a very effective way to save on disk space when combined with compression;

When files are the least active or have not been accessed for the longest period of time (eg. Exceeds a capacity threshold), data migration occurs.

Index

Improvements in the NetWare File System

Figure 10: Data migration

Index

Improved File System Security

Access to parts of the network directory tree are

controlled by explicit trustee assignments;

When a user logs in, he specifies the name of the

NDS object that represents the user account. The

user’s login name and password are used to build

a personalized key that is used to authenticate a

user’s right to access the network (figure 11);

IndexImproved File System Security

The user must pass the NDS security level. He must have certain rights to the volume object in the directory tree;

Then the user’s access to a file is controlled by the File and Directory Trustee rights.

Figure 11: NetWare 4.x security

IndexSupport for Network Auditing

In NetWare 4.x, a class of users called auditors can be set up to act independently of the network administrator in order to audit critical activities on the network;

The auditors can also audit past and present transactions on the network for any security breaches(figure 12);

Auditing allows the monitoring of critical events on the network, such as logins and logouts, file operations, directory services object operations(creations, deletions, reads and writes), directory object events, user events and trustee modifications.

Index

Support for Network Auditing

Figure 12: Auditing in NetWare 4.x

IndexSimplified and More Efficient Memory Management Architecture• In NetWare 3.x:

Memory management in NetWare 3.x is shown as figure 13; memory was managed in five pools, each serving a different purpose;

Figure 13: NetWare 3.x memory management

IndexSimplified and More Efficient Memory Management Architecture

• In NetWare 3.x: The pools were for purposes such as cache

movable, cache nonmovable, permanent

memory and semipermanent memory;

Memory pools were permitted to borrow memory

from the file cache buffer memory, but once

borrowed, this memory was not returned;

To reset the memory pools, the server had to be

restart.

IndexSimplified and More Efficient Memory Management Architecture• In NetWare 4.x:

There is only one main pool – the file cache memory (figure 14);

All memory used by processes running on the server are borrowed against this pool and completely returned to it when the process terminates;

Other processes can reuse the returned memory.

Figure 14: NetWare 4.x memory management

Index

Some of the features of NetWare 4.x memory management

Improved server performance, because memory

management is an important resource for server

processes;

Integration with the paged memory architecture of

the Intel processors;

Ring protection to control damage caused by

misbehaved NLMs (NetWare loadable module);

Easier-to-write applications for the NLM developer

because memory management is simpler.

Index

The Ring architecture of NetWare 4.x

The operating system kernel is running in Ring 0. All

NLMs run in Ring 0 by default but the network

administrator can configure server to run NLM that are

loaded in an outer ring (figure 15);

A program at Ring 3 would have to make an inter-ring

gate call to make service requests from the operating

system kernel;

If program crash, it cannot affect the kernel;

More reliable but reduce speed.

Index

The Ring architecture of NetWare 4.x

Figure 15: Interl 80386 processor ring architecture

Index

Improvements in Client Networking Services• NetWare 4.x includes better support for DOS,

MS Windows, and OS/2 (figure 16). DOS and MS Windows use a DOS requester, ODI support and Packet Burst Protocol support;

Figure 16: Multiple client support NetWare 4.x

Index

Improvements in Client Networking Services

DOS requester allows the redirector capability of later releases of DOS via the interrupt mechanism INT 2F (hex) to be used.

DOS requester consists of number of smaller components (called Virtual Loadable Modules and managed by VLM manager VLM.EXE) that need to be loaded only if the service is needed.

ODI support is the Open Data-Link interface that provides an interface for protocol stacks to talk to network boards, which represent layer 2(data-link layer) of the OSI model.

Index

Improvements in Client Networking Services

Packet Burst Protocol allows transmission of

multiple packet requests and packet replies. A

number of requests or replies can be

acknowledged by a single acknowledgement

packet.

NetWare 4.x supports for Large Internet

Packet(LIP) which means larger packet size that

are common in Token Ring networks(4 KB to 16

KB) and Ethernet networks (1.5KB) are possible.

IndexIntegrated Storage Management Services (SMS)

SMS provide for data on the network to be backed

up or restored in a common data format and in a

manner that is hardware- and software-

independent;

The device that needs to be backed up is called

the target. The target could be a workstation, a

NetWare 3.x server, or a NetWare 4.x server;

A Target Service Agent(TSA) program is run on

the target and communicates with the SBACKUP

program. (figure 17);

Index

Integrated Storage Management Services (SMS)

Figure 17: SMS and TSAs

Index

Integrated Storage Management Services (SMS)

In SMS, the SBACKUP program is responsible for

backup and restore operations. SBACKUP is an NLM

that runs on a NetWare server.

Other modules in SMS are Storage Management Data

Register(SMDR—used to pass commands between

SBACKUP and the TSAs), Storage Device

Interface(SDI—communicate between the SBACKUP

program and the storage devices). (figure 18)

Index

Integrated Storage Management Services (SMS)

Figure 18: SMS architecture

IndexImprovements in Network Print Service Architecture

Print jobs can be sent to the network print queue or be

sent to the printer object in the NDS tree;

Simpler installation in comparison to NetWare 3.x;

Support for a larger number of printers (up to 256) on a

single print server;

Support for remote printers on NetWare servers.

IndexMultiple Language Support (Internationalization)

NetWare 4.x has introduced support for international languages to NetWare Loadable Modules and network utilities.

Having different language NLMs running on the server at the same time or having one user using the system utility in French and another user using the same utility in Italian are even possible.

Does not mean NetWare is capable of translating messages between users using different languages.

IndexSimplified Installation and Upgrade Procedures NetWare 4.x distribution comes in CD-ROM.; The CD-ROM drive can be attached to the server being

installed, or to a remote workstation(figure 19); In the figure 19, the CD-ROM is shown as an external

unit to the workstation or server. Internal CD-ROMs also are possible.

Figure 19: NetWare 4 installation using CD-ROM distribution

Index

Conclusion

In some ways, NetWare 4.x is very similar to NetWare 3.x, but in other ways, NetWare 4.x represents a radical departure.

You can learn more about NetWare 4.x from the book “Migrating to NetWare 4.1”