Like
most of the other organisations, our University is experiencing
rapid growth in the use of IT at the time when reduction of
supporting manpower continues. Seeking ways to optimise the
effectiveness and efficiency of the available support work
force is inevitably the only solution to the problem. Server
consolidation on the operating system platforms, data storage
and the services has therefore been adopted as one of our
strategies to meet the challenge. Consolidation of servers
in the CityU is divided into three parts, namely Central Unix-based
application servers and storage, departmental Windows-based
LAN servers and storage, and Central Web and FTP servers.
A. Consolidation of Central Unix-based Application Servers
and Storage
Consolidation
involves the establishment of Unix servers, each capable of
being partitioned into virtual servers, to replace the old
and smaller servers together with the use of central network
storage system (mainly SAN which can efficiently handle large
databases or files with large size) as the common storage
instead of conventional direct attached storage for each individual
machine. The advantages of this approach are much simpler
management, more efficient operations, flexible data sharing,
high data availability, and real time on-demand expansion
of storage space, etc. All these lead to tremendous improvement
on the availability and reliability of the central servers
and data, and thus on the quality of the central services
which are critical and essential to the University operations.
The Consolidation began in 1999 and is now more or less completed.
At the
moment we have four Sun Enterprise class servers configured
with 23 domains (virtual machines) to provide support to the
most critical services in the University. These cover systems
for learning, teaching, communication, research, and administration.
These large Enterprise servers are grouped and configured
dynamically to enable load-balancing, clustering, high availability
and fault-resilient capability.
The storage
of all the central servers is provided by a large Network
Storage System and a Tape Library backup system from EMC.
The existing Storage Area Network (SAN) has 7-terabyte Storage
capacity and can handle scheduled and unattended backup of
all systems, LAN-lessly and server-lessly.
B.
Consolidation of Windows-based Departmental LAN Servers and
Storage
Our University
has some 60+ departmental servers running a mixture of Windows
NT 4.0 and Windows 2000 Server systems to support file services
to staff in various departments. At present, each departmental
server handles network service requests from only its own
departmental staff PCs, and all data and software are served
from individual local storage directly attached to it. Apart
from the problems of replication of operating system, software,
and patch updates to these departmental servers, to manage
effectively such vast volume of data scattered among the 60+
servers has become a great challenge to the Computing Services
Centre (CSC). To solve these problems, a few NT/Windows 2000
Server Clusters and a central network storage system (mainly
NAS which handles very efficiently the sharing of small files
or the I/O operations at file level) have been installed.
In fact, with these facilities, our Windows users can enjoy
the same quality services as those being offered to Unix users
by the Unix server clusters and SAN.
Our Windows
server clusters include Windows server farms from IBM and
Dell while the NAS system is an EMC Celerra with four Data
Movers and a total of 1.4 Terabytes storage. Starting this
September, the existing 60+ departmental file servers will
be gradually replaced by these Windows server clusters, and
their data also migrated to NAS accordingly.
C.
Central Servers for Hosting Web sites and providing FTP services
As you
may probably know, more than 450 Web or FTP servers of various
kinds have been set up and used in the University by various
departments. Most of these servers are used to provide services
to University users or the public accessed from within or
outside the University. As server management is undoubtedly
a complex and labour intensive task that demands high management
and technical skills, perhaps this explains why a number of
servers set up by users are often being hacked or infected
with viruses.
Central
Web Hosting and FTP Services are hence set up to provide a
consolidated, fully monitored and managed environment for
hosting departments' Web sites, project Web sites, or FTP
sites. As highly reliable and secure central servers will
be used to host these services, Web site owners or FTP service
providers can then concentrate on the development of their
contents without the need to worry about the server management
or operational support of the servers. It also releases these
owners from the burden of keeping the individual servers secure
and managing them.
It is
hoped that this centralised support arrangement can eradicate
the levels of risk of having so many Web and FTP servers distributed
around the campus with different security protections. The
consolidated infrastructure to host these Web and FTP sites
also leverages the economy of scale, thereby creating significant
cost savings.
The Central
Unix Web Hosting service has been in place for quite some
time with the Sun E6000 system to support the departmental
Web and Intranet applications. This will be upgraded to two
domains of E10000 in the form of load-balanced set up to meet
the demand of Unix based Web server hosting.
A Central
Intel-based Web Hosting server farm with database support
will also be set up and added to the hosting services. It
consists of the following: