1. GENERAL OVERVIEW
Pressure on Servers
Servers in a Distributed Environment
Review of OUCS
This year has again seen an increase in the use of OUCS, across almost all services. In some
cases, the magnitude of this increase has been dramatic. This has required active monitoring
of systems and servers to ensure that their level of performance is not adversely affected - in
several cases, upgrades have been installed. Despite increased use of automated systems,
which has prevented this demand from being reflected directly in the degree of added load on
staff, all OUCS staff are finding themselves under increasing pressure, and further changes
must be made (or additional staff resources acquired) if this pressure is not to become more
debilitating than it is already.
It is therefore perhaps worth unpicking these developments a little. Where is the demand
coming from? Is it legitimate? What trends are apparent in its magnitude and rate of change?
Is OUCS the right place for it to be directed? If not, what can be done to redirect the demand.
Are appropriate steps being taken by OUCS (and by the University as a whole through its IT
Strategy) to cope with such growth in demand? And so on.
Here may not be the right place to suggest answers to all these questions, because the General
Board has launched a Review of OUCS, which commenced at the end of this year, specifically
to address such matters. However it may be appropriate to provide some commentary as part
of OUCS' annual analysis of the year's activity.
The most dramatic growth has been in network services. Firstly, the numbers of computers
connected to the University network continues to grow linearly, reaching nearly 12,000 by the
end of the year (see Figure 2). This makes the University's network the second-largest in
Britain. The number of Ethernets connected also continues to grow steadily, with over 170
connected by the end of July (see Table 1), confirming its first rank among Ethernets in
The demand for services provided over these networks is, however, growing at a much more
rapid pace. For instance, the total Janet traffic is doubling in less than 12 months (both
inwards and outwards traffic), averaging 35 GBytes/day by the end of the year (26GB in, 9GB
out), but with daily peaks reaching 56 and 32 Gbytes respectively. It is noteworthy that the
vertical scale on Figure 4 is four times that used on the equivalent graph last year.
This is matched by the increase in volume of email traffic, which now exceeds 160,000
messages/day at times (see Table 3). Utilisation of such networked services as Web page
accessing and newsgroup reading also reflects these trends.
Pressure on Servers
Pressure on Servers
These volumes and rates of growth require serious and vigilant managing, with decisions being
taken during the year to set up dedicated servers for some of them. The lesson is that,
although the growth rarely imposes directly proportional increased load on staff, considerable
effort is nonetheless required to monitor workloads and ensure timely and smooth transitions
to improved platforms.
To a significant extent, this growth in use of networked services accounts for the upsurge in
use of the central Unix servers. Growth in use of Sable was such that, coupled with the
knowledge that it would be required to handle in addition the residual Vax load once it was
wound down, it became necessary to shed some of its load onto a second system, Ermine.
Combined use of these more than doubled (in terms just of interactive sessions) during the
In contrast with an earlier age, the predominant use of these systems currently is very probably
not "computing" as we have previously known it, but accessing networked services such as
email, newsgroups, Web activity, and ftp.
While there is undoubtedly good reason for distributing most subject-oriented computing,
there is still merit in centralising such generic use of IT services. OUCS has responded to this
growth by commissioning several special-purpose servers - for handling Janet traffic, for
network name serving, for email, for network news, for Web pages and caches. Typically,
these are small systems (often based on PCs running Linux), but still requiring a substantial
investment of staff support, as well sometimes of equipment, since their performance and
reliability has become so critical to so many.
Serversin a Distributed Environment
The above is one expression of a significant change which is taking place. As IT usage shifts
from simple use of central services (like the Vax), towards a distributed client-server mode of
operation, the central servers assume an equally important role in the provision of IT facilities.
The Hierarchical File Server quite clearly illustrates this trend towards "invisible" central
services. Users never use the HFS directly (in the sense of logging into it). Although they
may not be totally oblivious to its existence, its use is almost transparent to the user when it is
operating at its best. Increasingly, all manner of services provided by OUCS are thus used in
an unconscious fashion.
The above illustrates two of the main briefs of OUCS - (1) to provide and support basic
infrastructure, especially the network, and (2) to provide and support a range of
network-accessed services based on central servers.
The magnitude of use of the Unix servers demonstrates the extent to which the University is
still very much dependent on a third brief of OUCS, namely to provide "safety net" services -
general-purpose services for people who have not been provided for in some other way, eg
through their department or college.
Another important brief of OUCS is to provide expert back-up to distributed IT support staff.
Increasingly, we can expect that users will approach localised IT support in the first instance
when they run into difficulties or want to advance the level of their use of IT. Such local
support staff cannot usually be expected to have in-depth knowledge of every technology
being employed in their unit; they would normally be generalists, who could call upon
specialist technical backup when required.
Recognising that this is probably the most appropriate model for the future, OUCS has
undertaken several initiatives this year with a view to laying the groundwork for this to
develop. These include establishing a SIG for all IT support staff (with an emailing list and
newsgroup), arranging a joint meeting with Libraries staff, and suggesting and assisting in
mounting the first ever IT Support Staff Conference. Work has also been undertaken on
providing effective access to electronic information about the services OUCS provides, which
is a key element of our strategy to support and inform an expanding and diverse population of
IT users and local support staff. Plans have also been made to develop a framework for
service-level definitions, to ensure that there is sound understanding of the services and
obligations of OUCS, though little progress was possible during the year.
Amongst further attempts to reinforce the client-server mode of operation, OUCS has
bolstered and expanded the Shop, dramatically increased the software it acquires and
distributes under site-licensed and bulk-purchase agreements, and attended to growing
numbers of people with personal computer queries or problems.
In a related move, OUCS has, during the year, developed further its highly successful
self-Registration service, through which legitimate members of the University can acquire a
range of capabilities without visiting OUCS or even making direct contact with it. The
services for which users can currently self-register include Sable/Ermine accounts, access to
Dial-in, and Backup via the HFS. Other services are in the pipeline, including LaRC accounts,
Print services, Email routing and training course enrolments.
This Registration System has been so designed that, as well as allowing us simply to add
further services for which people can register, we will also in due course be able to allow local
support staff themselves, remotely, to change the parameters of the users they support.
Furthermore, it should also prove possible to allow such staff to use this system to maintain
account details of their local departmental or college systems, thus ensuring that there is
greater consistency about account details, allowing access to the high-quality database of
legitimate users of IT within the University that OUCS has developed, encouraging more
commonality of approach to supporting users, and paving the way for common security
standards such as Kerberos to be introduced.
All these initiatives illustrate the commitment OUCS has to promoting and supporting distributed, client-server computing, and a recognition of the development in its future role
within the IT panoply being built up across the University.
Review of OUCS
Review of OUCS
The Review of OUCS will provide the University (and OUCS itself) with a good opportunity to review these trends, their impact on OUCS, and the way in which OUCS has been responding. The Review will undoubtedly confirm the overall trends, and we trust will endorse the initiatives that OUCS has taken or planned in order to address the changes that are resulting.