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HOWTO:
Using an APC Uninterruptible Power Supply with Linux
by NorthBear Another heavy, wet spring snow storm is moving through the
mountains as I write this article. My APC Uninterruptible Power Supply
(UPS) has actived 20 times this morning. Without it, my life would be
miserable! Here is a nice HOWTO
for setting up an APC UPS for Linux.
The support package for APC UPS boxes is "apcupsd". The latest version is 3.14.0 and is available from APCupsd.org. Check the repositories for your Linux distro for the latest pre-compiled version, letting you avoid the bother of downloading and compiling the source code. The package also includes a GTK based GUI called "gapcmon" for monitoring the UPS. After you install acpupsd, you will want to edit the daemon's configuration file to provide the name of the UPS, the cable type, connection type and battery level for automatic shutdown. Here is what I changed in /etc/apcupsd/apcupsd.conf
for my system:
I decided to initiate shutdown when the battery reaches 20% rather than the default 5% since I have a machine with two hard drives and a 24" LCD monitor to keep powered up. Once you have configured acpupsd.conf, you will need to make
certain the daemon is activated when the system boots up. Use the
System Services tool supplied with your distro to activate the daemon.
This figure shows the tool Kmenu->Administration->Server
Settings->Services that is supplied with Fedora Core.
GAPCMON GUI Interface  Fig. 3 Active Monitors Panel The "UPS" icon provides access to the
following setup panels:
 Fig. 4 Active
Monitors Panel
The GUI can monitor multiple
apcupsd daemons, either locally or on remote machines using a LAN.
 Fig. 5 Monitor
Preferences Panel
The Preferences Panel allows you to control your various apcupsd monitors.  Fig. 6 Graph
Properties Panel
The Graph Properties Panel allows the
user to set the colors for the Historical
Summary Graph. This is the first panel for the second tray icon,
the one showing a power plug. The Glossary
and About panels are text help
files.
 Fig. 7
The Historical Summary GraphThe Historical Summary Graph charts battery voltage, line voltage, percentage of time left and percentage of load on the UPS. While nice, this doesn't appear to be a terribly useful feature. It's more for Pointy Haired Bosses!  Fig. 8 Detailed Information Panel The Detailed Information Panel has the "really good stuff". Timestamps for on/off battery, a cummulative time while on battery and the line voltage are very nice items to know. Too bad the battery isn't a "smart" one, otherwise we would know it's manufacture date.  Fig. 9 Power Events Panel The Power Events Log shows line events
and when the apcupsd daemon is shutdown.
 Fig. 10 Full
UPS Status Panel
The Full UPS Status Panel supplies even more information. Notice the "LOTRANS" and "HITRANS" values for dips and spikes in the line voltage. Conclusion
The
APC brand of
Uninterruptable Power Supplys is not the only brand of UPS available.
It is, however, the most widely available and has very good support
under Linux in addition to Windows.
The only annoyance with the apcupsd package that I can remark upon is the rather odd fact that the default configuration file is setup for a UPS with a serial interface. While these were the standard 6 or 7 years ago, all the APC UPSs that I've purchased over the past few years have been USB interfaces. If the default configuration were changed to USB and some additional code was written to support automatically naming the UPS, then the manual editing of the configuration file could be eliminated. The less editing, the better! I highly recommend that everyone get a UPS for their computers. It's a real lifesaver! |
Fig.
2 Activating apcupsd in Fedora Core