Uninterruptible Power Supply

Use

The local electricity utility generally provides power supplies. Although this is often highly reliable, the consequences of even very occasional failure mean that you should give high priority to the problem of reliability of supply.

Install uninterruptible power supply (UPS) as a fundamental aspect of ensuring high availability

UPS is relatively cheap and you should install it early on when building high availability into your SAP system.

Features

Consider the following to protect your system from power supply problems:

  • Continuity of supply

You can take the following measures to cope with complete failure of supply:

    • Install generator systems to provide continuous power in the event of supply failure. This is the most comprehensive solution to problems of supply continuity.
    • Install a battery backup system that can sense the failure of external power and switch to battery supplied power in the event of such a failure. Battery backup systems offer a limited time (approximately 10 to 15 minutes) during which the system can be sustained. In this scenario, a script is normally provided to shut down the system gracefully as the battery nears the end of its power. This graceful shutdown decreases recovery time, compared to a sudden system outage. If power returns prior to the shutdown of the system, the system switches to regular power and continues working without interruption.
  • Quality of supply

Additionally, you can install a power conditioning system in areas where the power supply is reasonably reliable, but might be subject to significant fluctuations in current. Variants of UPS are available to protect the hardware against various power supply problems (for example, spikes, surge, sags, noise, brownouts, blackouts, and harmonic distortion).