Today, the power problems facing a network manager are too numerous and too complex for a simple UPS-only solution. The most common power problems facing the network manager and user include:Loss of data/information Notification of utility outages and power related events Increasing network complexity Limited resources to manage the network The need to understand and diagnose power problems Today's sophisticated network power management software products, when used in conjunction with a UPS, can solve these problems. Alternatives and trade-offs between higher end software solutions and entry-level products will be examined. 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, "Forty-five 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 will provide power to the computer. 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 re-installed. With the potential for many users to be 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 events Aside from shutting down the computer properly, one of the next most important problems to address is rapid notification of people who are 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 or Sun Microsystems' SunNet Manager, 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 adaptor products is also a consideration. Network adaptor products connect an 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 adaptors 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 complexity As 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 WAN protection, users should select packages, which can communicate across network devices such as bridges and routers. Also, with mixed networks, such as 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 HP's 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 network With 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 6pm and restart on Mondays at 7am. 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 problems Of 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 represent 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 versus 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 online versus other technologies, and choose an appropriate network management software package. Conclusion Solving 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. Compiled by Mike Burkitt ( 1999 Powerware, Inc.
This was first published in October 1999