Installing an APC UPS on Linux [2005-09-13]

Live example

Geekscape web server UPS status (live link) ...

Multimon: UPS Status Page

APCUPSD UPS Network Monitor Wed Jun 19 12:27:56 EST 2013
System	Model	Status	Battery Chg	Utility	UPS Load	UPS Temp	Batt. Run Time	Data
Local Host	Not available: upsfetch: tcp_open failed for 127.0.0.1 port 3551

Sadly, the "Local Host" and "Live data" links don't work when embedded in this page, use the "live link" (as above) to delve deeper

Overview

For important systems, such as business and home automation systems, it is clearly a good thing to be resilient to short duration power failures and surges. These days, Uninteruptable Power Supplies (UPS) are fairly inexpensive, at around AUS$270 for a basic unit. They are very easy to set-up and fairly well supported under Linux. So, there is every reason to get one and few excuses for not doing so. You'll rest easier during that next thunderstorm !

I chose an American Power Conversion (APC) Back-UPS CS 500, which for my current needs, one web server and ADSL modem, is likely to provide around 20 to 30 minutes of coverage with a UPS load of approximately 20%.

Some basic suggestions are ...

Choose a smart UPS with a USB cable (or Ethernet connection), don't get one with a serial cable
Get as much capacity as you can afford without breaking the bank
UPS batteries don't last forever, test them every 6 to 12 months, but no more than that
Quoting ESR ...

If you acquire a APC UPS, then use apcupsd
If you acquire anything else, then use nut
BatteryWholesale.com ship new batteries to international customers

There is plenty of good documentation regarding UPS and Linux ...

The Linux Documentation Project UPS How-To (general information)
APC UPS Daemon on-line manual (apcupsd specific)
Network UPS Tools on-line documentation (nut specific)

Description

Tested using Linux Fedora Core 4

Set-up BIOS to always boot your system when power is turned on
Get latest apcupsd RPM from the dries yum repository ...

vi /etc/yum.repos.d/dries.repos
  [dries]
  name=Extra Fedora rpms dries - $releasever - $basearch
  baseurl=http://ftp.belnet.be/packages/dries.ulyssis.org/fedora/linux/$releasever/$basearch/dries/RPMS/
  enabled=1
  gpgcheck=1
rpm --import http://dries.studentenweb.org/ayo/RPM-GPG-KEY.dries.txt
yum install apcupsd apcupsd-debuginfo

Creates the following directories ...

/etc/apcupsd/ (daemon configuration)
/etc/httpd/conf.d/apcupsd.conf (web server configuration)
/var/www/apcupsd (web server CGI scripts)

Check that apcupsd is enabled during system boot ...

```
/sbin/chkconfig --list apcupsd
```

Connect your APC UPS to your server using the USB cable
Check that the USB device has been found ...

  
cat /proc/bus/usb/devices
    P:  Vendor=051d ProdID=0002 Rev= 0.06
    S:  Manufacturer=American Power Conversion
    S:  Product=Back-UPS CS 500 FW:808.q5.I USB FW:q5
    S:  SerialNumber=BB0505003566
    I:  If#= 0 Alt= 0 #EPs= 1 Cls=03(HID  ) Sub=00 Prot=00 Driver=usbhid

The udev rules should work out-of-the-box under Fedora Core 4

Configure apcupsd for a simple standalone configuration using USB ...

vi /etc/apcupsd/apcupsd.conf
  UPSCABLE usb
  UPSTYPE usb
  DEVICE
  LOCKFILE /var/lock
  UPSCLASS standalone
  UPSMODE disable

Configure your system halt script to power off the UPS ...

This patch should have occurred as part of the yum installation, but I had to do it manually
Insert the following towards the end of the script, after remounting the disks readonly and just before halt or reboot

vi /etc/rc.d/init.d/halt
  # See if this is a powerfail situation.                     # ***apcupsd***
  if [ -f /etc/apcupsd/powerfail ]; then                      # ***apcupsd***
     echo                                                     # ***apcupsd***
     echo "APCUPSD will now power off the UPS"                # ***apcupsd***
     echo                                                     # ***apcupsd***
     /etc/apcupsd/apccontrol killpower                        # ***apcupsd***
     echo                                                     # ***apcupsd***
     echo "Please ensure that the UPS has powered off before rebooting"
     echo "Otherwise, the UPS may cut the power during the reboot!!!"
     echo                                                     # ***apcupsd***
  fi

Start the apcupsd daemon ...

```
/etc/rc.d/init.d/apcupsd start
```

Check that the apcupsd daemon has started correctly ...

cat /var/log/apcupsd.events
  Sun Sep 11 03:07:57 EST 2005  apcupsd 3.10.18 (21 July 2005) redhat startup succeeded
apcaccess status

Perform various UPS tests ...

See Apcupsd User's Guide: Testing apcupsd ...

Process-Status Test
Logging Test
apcaccess Test
Communications Test
Simulated Power Fail Test
System Shutdown Test
Full Power Down Test

Test the APC UPS hardware ...

The apcupsd needs to be stopped before beginning the hardware test

/etc/rc.d/init.d/apcupsd stop
apctest
  2005-09-11 02:34:41 apctest 3.10.18 (21 July 2005) redhat
  Checking configuration ...
  Attached to driver: usb
  sharenet.type = DISABLE
  cable.type = USB_CABLE

  You are using a USB cable type, so I'm entering USB test mode
  mode.type = USB_UPS
  Setting up the port ...
  Creating the device lock file ...
  Hello, this is the apcupsd Cable Test program.
  This part of apctest is for testing USB UPSes.
  Getting UPS capabilities...SUCCESS

  Please select the function you want to perform.
  1) Test kill UPS power
  2) Perform self-test
  3) Read last self-test result
  4) Change battery date
  5) View battery date
  6) View manufacturing date
  7) Quit
  Select function number: 7
  2005-09-11 02:35:06 End apctest.
/etc/rc.d/init.d/apcupsd start

The apcupsd needs to be restarted at the conclusion of the hardware test

Provide UPS status via your web server ...

The yum installation should have created ...

/etc/httpd/conf.d/apcupsd.conf (web server configuration)
/var/www/apcupsd/ (web server scripts)

vi /etc/httpd/conf/httpd.conf
  Include /etc/httpd/conf.d/apcupsd.conf

Test web server apcupd scripts using your web browser ...

firefox http://localhost/apcupsd/multimon.cgi?refresh=300  # Default is to refresh the HTML page every 30 seconds
firefox http://localhost/apcupsd/upsfstats.cgi
firefox http://localhost/apcupsd/upsstats.cgi

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