Configuring HP-UX For Peripherals
Chapter 9 227
Configuring Uninterruptable Power Systems
Configuring a PowerTrust UPS
b. Add a comment sign (#) in front of the getty entry corresponding to
the port used by the UPS. For example,
#ttp1:2:respawn:/usr/sbin/getty -h tty0p1 9600
Step 4. Edit the /etc/ups_conf file to customize the UPS configuration for your
system. The etc/ups_conf file informs the monitoring daemon
(/usr/lbin/ups_mond) which ports to monitor and how to react to UPS
status. The ups_conf (4) manpage documents the required format and
available options. Also, read carefully the guidelines for setting
shutdown options just ahead.
shutdown_delay_mins:1
shutdown_timeout_mins:5
upstty:/dev/tty0p1
upstty:/dev/tty0p2:MSG_ONLY
a. To ensure that the UPS operates appropriately to your system, review
carefully the guidelines listed below concerning how to set
shutdown_delay_mins and shutdown_timeout_mins in the
/etc/ups_conf file:
• shutdown_delay_mins (one minute, by default) is the number of
minutes after loss of AC power is detected before HP-UX invokes
shutdown -h. Increase this value if the site commonly experiences
momentary power interruptions greater than one minute for
which recovery of power is expected.
• On a large system, do not set the shutdown_delay_mins to a value
larger than nine minutes. HP guarantees the UPS to provide
output power for up to fifteen minutes. Large systems may take as
long as five minutes to complete shutdown plus one minute for the
shutdown grace period. Thus, to ensure that the UPS provides
power for the entire operation, figure maximum
shutdown_delay_mins as fifteen minus six, or a difference of nine
minutes.
• shutdown_timeout_mins (five minutes, by default) is the number
of minutes shutdown -h is expected to take. UPS terminates
power supply one minute after this value elapses. If shutdown
does not complete in the time specified, the UPS monitor initiates
a reboot -h to halt the system.
• Increase shutdown_timeout_mins if shutdown takes longer than
five minutes, including the one minute grace period.