Configuring HP-UX For Peripherals

226 Chapter9

Conﬁguring Uninterruptable Power Systems

Conﬁguring a PowerTrust UPS

The simplest way to conﬁgure a uninterruptable power system is to use

SAM (/usr/sbin/sam). If SAM is not loaded on your system or if you

prefer to use the command-line interface, the following procedure will

guide you through the task. Familiarize yourself with the instructions

before getting started.

Step 1. Examine Table 9-2, “UPS Conﬁguration Requirements,” to identify the

driver and interface card associated with the speciﬁc platform to which

you are conﬁguring the UPS. Under virtually all circumstances, the

interface driver used by the UPS is already present in the kernel.

Step 2. Invoke ioscan for the tty class to display the hardware path, driver, and

device special ﬁle(s) available for the UPS. Your output might resemble

the following:

/usr/sbin/ioscan -fun -C tty

Class I H/W Path Driver S/W State H/W Type Description

================================================================

tty 0 56.0 mux4 CLAIMED INTERFACE

/dev/tty0p0 /dev/tty0p1

In this (simpliﬁed) example from a Model 887, the multiplexer card is

installed in slot 14 (H/W Path divided by 4) and bound with the mux4

device driver. Device special ﬁles /dev/tty0p0 and /dev/tty0p1 are

available. If an MDP or DDP is installed at the MUX port, ioscan will

show device special ﬁles for all the ports available.

As shipped, the console is conﬁgured to be plugged in at port 0. The

/dev/console ﬁle is equivalent to /dev/tty0p0. Thus, in this example,

Port 1 (represented by /dev/tty0p1) can be used for the UPS.

Step 3. Edit the /etc/inittab ﬁle to activate the UPS monitoring daemon when

the system boots up. To do so,

a. Remove the comment sign (#) from the UPS entry. Be sure the ups

entry appears after the /sbin/rc entry, so that the ups_mond is

started after the system logging daemon (syslogd). Note, the UPS is

started with real-time priority so that it does not get "starved" on a

busy system.

ups :respawn:rtprio 0 /usr/lbin/ups_mond -f /etc/ups_conf