Solving power protection problems in today’s increasingly complex
environment requires a total system approach combining UPS hardware
and power management software
Loss of data/information
The first and most important problem facing the network manager is
the loss of data or information. In fact, according to Contingency
Planning Research, "45 per cent of computer data loss in the US is
due to power outages and surges." Protection by a UPS is adequate
unless the power outage lasts longer than the battery in the UPS.
Should a computer suddenly be without power it, of course, stops
functioning. With some sophisticated operating systems, such as
UNIX, the impact goes beyond simply the system turning off. Mission
critical data files and even the operating system itself can be
corrupted leaving the network manager or user with the task of
trying to figure out what has been affected and then taking the
necessary corrective action. It may even require that the operating
system be reinstalled. With the potential of many users being
unable to perform their respective tasks while waiting for the
problems to be resolved, the company faces significant loss of
productivity and the resulting revenue and profits.Today's network
power management software products, whether it be high end or entry
level, all provide for a graceful shutdown of the operating system
and closing of all open applications and files in the event of an
extended electrical failure, thus protecting the critical
information from loss or corruption. They also provide configurable
shutdown parameters, which allows the user to select how much time
to spend on battery prior to beginning the shutdown process, and
usually turn off the UPS to prevent complete discharge of the
battery, which shortens battery life. By choosing a more
sophisticated package, a shutdown sequence may also be customised
to execute a particular command prior to bringing down the system.
This feature allows for stopping applications in order of a
priority scheme determined by the user.
Notification of utility
outages and power related eventsAside from shutting down the
computer properly, one of the next most important problems to
address is rapid notification of people affected by a changing
power condition. The first and most important feature is
notification of users so that they have an opportunity to save
their work before the system shuts down. This feature is standard
in most power protection software packages. With more advanced
packages, notification via email or paging is included. This allows
a network manager to be notified, remotely, of a power related
problem and provides an opportunity to perform any specific system
management activities prior to shutdown either on-site or using a
remote connection.A high-end package may also provide notification
via Simple Network Management Protocol (SNMP) traps. SNMP is an
evolving standard for network management which has seen increasing
acceptance recently. A trap is a message which is sent to an SNMP
supported network management software package, such as IBM's
NetView for AIX, Hewlett Packard's OpenView, Sun Microsystems'
SunNet Manager, etc., which gives a brief statement/alert
describing power condition. In this manner, a network manager
receives the information in a form consistent with other
network-related messages.Communication with network adapter
products is also a consideration. Network adapter products connect
a UPS directly to a network which allows for protection of
non-computer devices. By using a network power management software
package, a network manager can monitor and reboot a remote UPS,
cycling power to a device which initiates a reset (sometimes
required to get a device to function properly). This feature
provides control of a UPS (and protected equipment) which may be
literally half-the-world away. Some more advanced software packages
also permit communication with adapters to allow multiple computers
to be powered by one UPS and still shutdown properly upon utility
failure. Potential cost and space savings may be realised through
this configuration.Network managers should look at the needs for
notification carefully, paying particular attention to potential
future requirements, such as SNMP communication, when selecting a
network power management software package.
Increasing network
complexityAs networks become more complex, network managers
have the increasingly difficult task of maintaining consistent
software solutions across hardware platforms. Whether an entry
level, basic package is selected or a higher end package is used, a
software vendor needs to support the wide variety of operating
systems that may be found across an enterprise. For true wide area
network protection, users should select packages that can
communicate across network devices such as bridges and routers.
Also, with mixed networks, such those having computers running both
NetWare and UNIX, becoming more prevalent, packages which provide
this internetworking capability are certainly worth careful
consideration. Integration with network management software
packages, such as NetView for AIX or HPs OpenView, can be desirable
because it means easier operation. A graphical user interface (GUI)
also helps speed installation, configuration and use of the
software.
Limited resources to manage the networkWith today's
downsizing and streamlining of organisations coupled with the trend
toward distributed computing, network managers are faced with the
fact that they will be expected to effectively manage an
increasingly complex network with no proportional increase in
resources or, perhaps, even fewer resources. In a situation with a
large number of protected computers or network devices spread
geographically, one of the most important features to look for is
remote monitoring capability. Using remote monitoring and advanced
features, such as notification via SNMP traps, network managers can
monitor the power enterprise-wide from a single workstation. In
some higher end packages, remote retrieval of battery information
is also possible making planning for maintenance of UPSs much
easier. Advanced packages also should contain a scheduled
shutdown/restart feature which will safely shutdown and restart the
system on a daily, weekly or on an exception (for holidays) basis
for energy conservation or security purposes. For example, a user
could select to shutdown a server (and power-off the UPS) Fridays
at 6 PM and restart on Mondays at 7 AM. Depending on the rate of
power consumption and power cost, significant power cost savings
could be realised. System security is increased because the
computer and UPS are automatically brought down and powered-off
during times when no users are present.
Need to understand and
diagnose power problemsOf all the topics related to power
protection, detecting and solving power problems before they happen
is perhaps the most desirable and the most difficult to achieve.
Advanced network power management software packages do take a first
step at tackling this issue by providing a log of power events that
have occurred over a period of time. Using this data, an analysis
can be performed to spot trends and resolve chronic power problems.
Some advanced packages also contain a battery test that can be
performed automatically every month, for example, to get an early
warning of a potential battery problem. To visually see power
parameters and detect and diagnose power quality problems, some
advanced packages also contain real-time meters and power waveform
graphs. The meter graphs show values for typical power parameters,
such as voltage and frequency over time. A power waveform graph
gives a visual indication of power quality by a comparison of the
incoming sine wave vs. the outgoing sine wave. A calculation of the
total harmonic distortion (a measure of power quality) can also be
performed. These features are useful to the more advanced,
power-oriented user to analyse power issues.Although these features
are useful to analyse repeated power problems, there is no way to
foresee a totally random event. The best method to protect a system
is to select a UPS which has the level of protection desired,
considering the benefits of on-line vs. other technologies and
choose an appropriate network management software
package.
ConclusionSolving today's power protection problems,
in an increasingly complex environment, requires a total system
approach combining UPS hardware and power management software.
Network managers should carefully consider the problems they face
and select the software solution that not only meets today's needs
but also allows for possible expansion, including such features as
the use of a standard communication protocol and diagnostic tools.
Developing a checklist of the "must have" and "nice to have"
features is one simple way of ensuring that the needs for power
protection are met.
Brad Wyckoff, software product manager,
Powerware, Inc.Compiled by Mike Burkitt