Server systems

The present invention comprises a system for the control of multiple remote resources. A plurality of user stations, each comprising a keyboard, video screen and a mouse, communicate with a server management unit. The server management unit is comprised of a server chassis, matrix switch and a switch server. Remote resources are each connected to a port of a multiplexer or to a server interface. A user station connects to a remote resource by making a request to the server management unit. The switch server identifies the multiplexer or server interface port to which the resource is connected from a database. A request is made to a remote interface server connected to the multiplexer and server interfaces and the remote interface server connects the appropriate ports of the server management unit and the multiplexer or server interface.

TECHNICAL FIELD OF THE INVENTION

This invention relates to the control of computer systems with multiple resources, for example multiple servers.

BACKGROUND OF THE INVENTION

There are many client/server systems which make use of a large number of servers; for example Internet Service providers, data warehouses, and software development laboratories. The management, control and maintenance of such multi-server systems can be complex and expensive.

One known arrangement is the FreeVision ™ system, which is the subject of W099/22294. This system enables workstations consisting only of video screen, keyboard and mouse to be connected to control any selected server using only serial signals over category 5 cabling. This system offers considerable advantages, but can only be used where the servers are capable of producing and handling keyboard-video-mouse (KVM) signals.

SUMMARY OF THE INVENTION

One object of the present invention is to enable the provision of a system in which a user work station can communicate with and control any selected one of a number of “headless” servers which do not themselves provide video format signals.

More generally, the present invention is concerned with enabling a user operating in one format to communicate with a resource (which may be a server or another machine, or a software resource such as a database) operating in another format in a manner which is automatic and transparent to the user.

Accordingly, the present invention provides a data processing system including one or more user stations each capable of sending and receiving data in a first form; a plurality of resources each capable of sending and receiving data in a second form; at least one helper computer arranged to transform data between the first and second forms; and a multiplexer for connecting the helper computer, or one of the helper computers, between a user and a selected resource.

From another aspect, the invention provides a method of operating a data processing system, which system comprises one or more user stations each capable of sending and receiving data in a first sending and receiving data in a second form.

Other objects, features, and characteristics of the present invention, as well as the methods of operation and functions of the related elements of the structure, and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following detailed description with reference to the accompanying drawings, all of which form a part of this specification.

Preferred features and advantages of the invention will-be apparent from the following description and claims.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As required, a detailed illustrative embodiment of the present invention is disclosed herein. However, techniques, systems and operating structures in accordance with the present invention may be embodied in a wide variety of forms and modes, some of which may be quite different from those in the disclosed embodiment. Consequently, the specific structural and functional details disclosed herein are merely representative, yet in that regard, they are deemed to afford the best embodiment for purposes of disclosure and to provide a basis for the claims herein which define the scope of the present invention. It should be noted that those individuals skilled in the art may be able to make some modifications of the preferred embodiments but which are based upon the underlying teachings contained within the subject invention.

Referring toFIG. 1, the system includes a number of servers, nine of which are shown at10. In practice, the system may include several hundred or more servers. The system also includes a number of user stations, one of which is shown at12. In practice, there might be some tens of users. Each user station comprises a keyboard, a video screen, and a mouse, each of which communicates with an interface20. The interface20permits keyboard-video-mouse (KVM) signals to pass to and from the user10via a path22using the FreeVision™ protocol.

It is desired to enable any user12to be connected with any server10in such a way that the user controls the selected server as though its keyboard, video screen and mouse were physically connected direct to the server. In this example, the servers10do not produce video signals in a displayable format such as VGA. The invention is based on interposing a helper computer between the user and the selected server to emulate the missing functions. It would, however, be unnecessarily complex and expensive to provide a computer for each server, or for each work station, and therefore a limited number of helper computers (which could be one, but will typically be single figures) is incorporated in the system so as to be efficiently used, as will now be explained.

Each of the servers10is connected to a respective port of a serial multiplexer (mux)28. The serial mux28in this example is a fully non-blocking 16-to-many serial mux. It must be able to switch any serial port to any TCP/IP session. Suitable multiplexers to meet these criteria are well known in the art. Also connected to the serial mux28are a number of helper PCs, two of which are shown at30, which in turn are connected to a server interface card32.

The users12are connected via a user interface card24to a server management system (SMS) which consists of a switch formed by a matrix switch27and a server chassis34, a switch server26, and an SQL database29for the switch server26.

The matrix switch27enables a given user port on the user interface card24to communicate with a given server port on the server interface card32.

Matrix switches of this nature are known per se, and are available for example from CCC Network Systems of Farnborough, Hants, England and Belfast, Northern Ireland. The matrix switch27is similar to that described in WO99/22294.

The switch server26is also arranged to communicate by an appropriate protocol, in this embodiment TCP/IP, with the helper PCs30and with the serial mux's28.

In a practical embodiment, there may be a large number of mux's such as28, each of which will have up to 16 servers connected to it, and can have any of a number of PCs connected via TCP/IP.

When a user requests access to a particular server, the following sequence of events will be performed:(1) The switch server26identifies from the database29the mux28to which the requested server is connected.(2) The switch server26then makes a request for connection.(3) According to the availability of each PC, the system attempts to propagate the request to any PC in the pool of PCs.(4) Once a free PC has identified itself, the switch server26instructs the PC which mux and port to connect to, which connects the appropriate corns ports (provided not in use).(5) The selected PC is instructed to start a terminal session with a shell command, which may usefully be stored as a string in the database29.(6) The PC confirms successful command execution, and the switch server26connects the user via the user interface card24, the switch27,34, and the appropriate port of the server interface card32.

To allow communication with the switch server26, and to enable requests to be propagated amongst the PCs, each of the PCs contains an Ethernet card (or similar networking arrangement). Each PC also has socket listening software to accept requests from the SMS and to allow termination of the session at any time. Upon termination, all links can be broken.

The arrangement described with each PC returning its location or ID allows any number of helper PCs to be connected to the mux. A smaller number of PCs reduces cost and complexity, while a higher number minimises blocking. Expansion is simple, merely requiring an additional PC and additional data in the database. Any PC can connect to any mux via TCP/IP. Thus there is a flexible pool of resources.

The system as thus far described therefore enables any user to be connected to any desired server via a helper PC. The servers10in this embodiment are headless servers which do not provide formatted video signals and may not be organised to accept keyboard and mouse signals directly. The helper PC is therefore provided with terminal emulator software, so that the combination of the user workstation12and the terminal emulator acts as a fully featured terminal to control the selected server.

FIG. 1also shows a server110which is capable of handling KVM signals, to illustrate that this can be connected directly to a port of the server interface card34without the intervention of a helper PC.

In the embodiment shown, the pathways labelled “KVM” carry KVM signals in analogue format. Other channels as shown operate in RS232. In a large system, this greatly simplifies cabling arrangements. However, other data transfer protocols may be used.

Our present preference is to use Linux as the PC operating system, as this avoids licensing restrictions and a large number of Unix terminal emulator programs are freely available. However, this preference is essentially commercial, and it will be appreciated that a wide choice of operating systems and emulator software would be suitable.

Thus, the PC and its installed software enable the user to interface with the server by proxy, and the PC may be referred to as a “proxy helper”. The same basic technique may be used to allow interfacing by proxy with resources other than servers, “resource” in this context being used to mean any machine or database. The proxy helpers could, for example, contain web browsers to interact with web-enabled devices, or custom interfacing software to interact with, for example, air conditioning systems or alarms. The switch server will know from its database the type of resource the user requires access to and will use this information to identify a suitable proxy helper PC from its pool.

In the prior art system of WO99/22294 the helper PC acts as a computer dedicated to navigation of a large multi-user computer system. The user invokes the helper PC, identifies a list of computers he requires access to (known as a profile), and then leaves the helper PC. At this point, the switch server takes over control and allows the user to move between the computers in his profile with no further helper PC involvement. Thus, the prior art system is intentionally invoked by the user, and is used temporarily to create or modify a profile.

In the present invention, the user does not intentionally invoke the proxy helper; this is an automatic action performed by the switch server based on the type of resource the user wishes to interact with. Proxy helpers are allocated on a per-session basis. Thus, the proxy helpers are intelligently utilised by the switch server based on resource type, and the operation is transparent to the user.

The system as described is very flexible and may readily be expanded and altered without requiring much if anything in the way of specialised hardware or software.

While the present invention has been described with reference to one or more preferred embodiments, such embodiments are merely exemplary and are not intended to be limiting or represent an exhaustive enumeration of all aspects of the invention. The scope of the invention, therefore, shall be defined solely by the following claims. Further, it will be apparent to those of skill in the art that numerous changes may be made in such details without departing from the spirit and the principles of the invention. It should be appreciated that the present invention is capable of being embodied in other forms without departing from its essential characteristics.