IBM RS6000 Service Guide - Page 304

System Power-On Methods Power-on Switch - see 'Starting the System Unit' in &ugtitle.. SP Menu power-on request You can request a power-on via the Service Processor menus from either a local or remote terminal. If a remote terminal is to be used, the modem must be connected to serial port 1, and the operating system set up to enable a TTY login session on that port. Refer to "Seamless Transfer of a Modem Session" on page D-6 for information on transferring modem sessions from Service Processor to the operating system. Unattended start mode - refer to Enable/Disable Unattended Start Mode on page B-12. The Service Processor can be enabled to recover from the loss of AC power (see Enable/Disable Unattended Power-On Mode in the SYSTEM POWER CONTROL MENU). When AC power is restored, the system returns to the then current power state at the time AC loss occurred. For example, if the system was powered-on when AC loss occurred, it reboots/restarts when power is restored. If the system was powered-off when AC loss occurred, it remains off when power is restored. Timed power-on - refer to the shutdown -t command on servers using AIX. Working in conjunction with AIX, the Service Processor in your server can operate a timer, much like the wake-up timer on your clock radio. You can set the timer so that your server powers on at a certain time after shutting down. The timer is battery operated, so power interruptions occurring while the server is off do not affect its accuracy. Refer to the shutdown -t command of AIX for details on setting the timer. Because of the potential for AC power loss, the Timed Power-On function of AIX can only be assured when Unattended Power-On Mode is enabled. If a Timed Power-On event occurs during an AC power loss, and if Unattended Power-On Mode is enabled, the system starts when AC power is restored. If Unattended Start Mode is disabled (the default), the system power state remains off when AC power is restored, regardless of the power state of the system when AC loss occurred. Ring Indicate Power-On Enabling ring indicate power-on disables remote call-in. If ring indicate power-on is enabled, the server will power on at a predetermined number of rings. If the server is already on, no action is taken. In either case, the telephone call is not answered. The caller receives no feedback that the server powered on. B-26 Service Guide