In this post we will try to install the Network UPS tools on a Raspberry-Pi device, attach a USB connected UPS and use it as a UPS server that will allow all machines sharing the same UPS to shut-down correctly when the UPS runs out of power. Our server will look after two clients; one running EL5 and the other openSUSE 11.4.
At the end of the post we will demonstrate how easy it is to set up your clients once the server is up and running and provide additional instructions for setting up the client software on Fedora 18 and EL6.
Before we begin I would like to confess that my first attempt to install a no-name made in China UPS resulted to total failure, so eventually I got an expensive APC BackUPS Pro, that worked without any problems from the beginning, so unless your UPS is one supported by the UPS network tools project drivers, don't even try to follow the tutorial.
A second remark, is that if you are following the tutorial as the standard pi user you will need to prefix almost all commands with sudo. To become root on a standard Raspbian and follow along, you will need to issue
sudo su-. (Thanks Derek for pointing it out)
root@raspbx:~# apt-get install nut-client nut-server Reading package lists... Done Building dependency tree Reading state information... Done The following extra packages will be installed: libupsclient1 Suggested packages: nut-cgi nut-snmp nut-dev nut-xml The following NEW packages will be installed: libupsclient1 nut-client nut-server 0 upgraded, 3 newly installed, 0 to remove and 0 not upgraded. Need to get 1,583 kB of archives. After this operation, 3,217 kB of additional disk space will be used. Do you want to continue [Y/n]? y Get:1 http://archive.raspbian.org/raspbian/ wheezy/main libupsclient1 armhf 2.6.4-2.3 [106 kB] Get:2 http://archive.raspbian.org/raspbian/ wheezy/main nut-client armhf 2.6.4-2.3 [191 kB] Get:3 http://archive.raspbian.org/raspbian/ wheezy/main nut-server armhf 2.6.4-2.3 [1,286 kB] Fetched 1,583 kB in 2s (562 kB/s) debconf: delaying package configuration, since apt-utils is not installed Selecting previously unselected package libupsclient1. (Reading database ... 37855 files and directories currently installed.) Unpacking libupsclient1 (from .../libupsclient1_2.6.4-2.3_armhf.deb) ... Selecting previously unselected package nut-client. Unpacking nut-client (from .../nut-client_2.6.4-2.3_armhf.deb) ... Selecting previously unselected package nut-server. Unpacking nut-server (from .../nut-server_2.6.4-2.3_armhf.deb) ... Processing triggers for man-db ... Setting up libupsclient1 (2.6.4-2.3) ... Setting up nut-client (2.6.4-2.3) ... [info] nut-client disabled, please adjust the configuration to your needs. [info] Then set MODE to a suitable value in /etc/nut/nut.conf to enable it. Setting up nut-server (2.6.4-2.3) ... [info] nut-server disabled, please adjust the configuration to your needs. [info] Then set MODE to a suitable value in /etc/nut/nut.conf to enable it. root@raspbx:~#
Don't worry about the nut-server information we shall deal with it later on. Now an optional step that will allow us to to use the
lsusb utility will be to install the
usbutils package, assuming that it is not already there. So:
root@raspbx:~# apt-get install usbutils
.. and then -- blame me for my Windows habits, I firmly suggest a reboot. When the system is back on, we will make sure that out USB device is nιcely plugged in...
root@raspbx:~# lsusb Bus 001 Device 002: ID 0424:9512 Standard Microsystems Corp. Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. Bus 001 Device 004: ID 051d:0002 American Power Conversion Uninterruptible Power Supply root@raspbx:~#
Our UPS is there so let's set up the driver for the nut server. Open file
/etc/nut/ups.conf and append the following lines at the end.
[apc1200] driver = usbhid-ups port = auto desc = "APC Back UPS Pro 1200VA supporting the two network servers"
You can name your ups anything you like, as far as the driver is concerned my advice is to browse through the official Network UPS Tools drivers list.
Setting up the UPS name and driver is not enough. I have not tested this on any other Debian box, but on raspberry-pi we need an extra step in order to create the
/var/run/nut folder and set correct permissions to it.
root@raspbx:~# mkdir /var/run/nut root@raspbx:~# chown root.nut /var/run/nut/ root@raspbx:~# chmod 770 /var/run/nut/
Now we are ready to test the UPS driver.
root@raspbx:~# upsdrvctl start Network UPS Tools - UPS driver controller 2.6.4 Network UPS Tools - Generic HID driver 0.37 (2.6.4) USB communication driver 0.31 Using subdriver: APC HID 0.95 root@raspbx:~#
Our next step will be to configure
upsmon. The network UPS tools design dictates that
upsd communicates with the UPS driver that we just started and
upsmon communicates with
upsd and actually shuts down the machine in the event of a power failure. By providing this extra level of indirection, nut allows for multiple instances of
upsmon to run on different machines. That way they can allow share the same physical UPS and this is what we said that we are going to demonstrate in this posting.
So to enable accessing the
upsd via the network, edit the file
/etc/nut/upsd.conf and place the following LISTEN directives.
LISTEN 127.0.0.1 3493 LISTEN 192.168.1.137 3493
192.168.1.137, is my pi's IP address -- replace that with your own. Next, we will need to add some kind of security and the next file that we will need to tamper with will be the
/etc/nut/upsd.users. Edit it with your text editor and set up the following users
[admin] password = myadmpass actions = SET instcmds = ALL # # --- Configuring for a user who can execute tests only # [testuser] password = pass instcmds = test.battery.start instcmds = test.battery.stop # # --- Configuring for upsmon # # To add a user for your upsmon, use this example: # [upsmon_local] password = local_pass upsmon master [upsmon_remote] password = remote_pass upsmon slave
Finally the local UPS monitor daemon will need to specify the UPS to monitor and the user credentials from
upsd.users file. Open the
/etc/nut/upsmon.conf file, locate the monitor section and add the following line:
MONITOR apc1200@localhost 1 upsmon_local local_pass master
The number 1 after the ups name and host is the power value. The man page for upsd states clearly that:
The "current overall power value" is the sum of all UPSes that are currently able to supply power to the system hosting upsmon. Any UPS that is either on line or just on battery contributes to this number. If a UPS is critical (on battery and low battery) or has been put into "forced shutdown" mode, it no longer contributes.
A "power value" on a MONITOR line in the config file is the number of power supplies that the UPS runs on the current system.
Final steps: Open the
/etc/nut/nut.conf file and change the value of Mode to netserver -- making sure that there are no spaces between each side of the = sign. (See NOTE at end of file) and issue the following commands:
root@raspbx:/etc/nut# service nut-server start [ ok ] Starting NUT - power devices information server and drivers: driver(s). upsd. root@raspbx:/etc/nut# service nut-client start [ ok ] Starting NUT - power device monitor and shutdown controller: nut-client. root@raspbx:/etc/nut#
As a last check, verify that both services will start automatically on system (using the
update-rc.d command) reboot and yes, our server is ready! ...
root@raspbx:~# ps -ef | grep ups nut 3275 1 0 Apr09 ? 00:08:24 /lib/nut/usbhid-ups -a apc1200 nut 3278 1 0 Apr09 ? 00:00:19 /sbin/upsd root 3312 1 0 Apr09 ? 00:00:00 /sbin/upsmon nut 3314 3312 0 Apr09 ? 00:00:09 /sbin/upsmon root 4721 4711 0 18:44 pts/1 00:00:00 grep ups root@raspbx:~#
Client setup requires more or less three things: One will be to edit the nut.conf file and set the mode variable value to
netclient. Next will be to place the correct MONITOR line in the
upsmon.conf file and the third will be to start the
Our first client is an openSUSE 11.4 machine that I keep saying that I must upgrade. To install nut on openSUSE we need to issue the following command as root.
zypper install nut
openSUSE nut stores the configuration files
/etc/ups. By the way the file
/usr/share/doc/packages/nut/README.SUSE offer excellent detailed and precise information on how to do things right. So to get things started:
Add the line
MODE=netclientat the end of the
MONITOR apc1200@asterisk "UPS supporting the main Servers"to
Comment out any reference to any UPS at the end of
MONITOR apc1200@asterisk 1 upsom_remote remote_pass slave
Start the service with
etc/init.d/upsd start. (The reload option can be used to reread updated configuration files
Finally change the system config so that the service starts every time you start your system using the following command:
chkconfig upsd on
Reboot and verify :
atlas:~ # ps -ef | grep ups root 2958 1 0 18:06 ? 00:00:00 /usr/sbin/cupsd -C /etc/cups/cupsd.conf root 3374 1 0 18:06 ? 00:00:00 /usr/sbin/upsmon upsd 3376 3374 0 18:06 ? 00:00:00 /usr/sbin/upsmon root 4776 4732 0 18:13 pts/0 00:00:00 grep ups
You might probably want to test the configuration and whether the upsmon daemon can shut-down your server, so go ahead and ...
atlas:~ # upsmon -c fsd Network UPS Tools upsmon 2.6.0 Broadcast Message from upsd@atlas (somewhere) at 13:57 ... Executing automatic power-fail shutdown Broadcast message from root@atlas (Wed Apr 10 13:57:06 2013): The system is going down for system halt NOW!
Perhaps the easiest setup is on a Debian system. You only need four steps:
Install just the client:
sudo apt-get install nut-client.
Edit the file
/etc/nut/nut.confand set the mode to netclient.
MODE=netclient(mind that there must be no spaces around the equals sign).
Add the monitor
MONITOR apc900@xena 1 upsom_remote remote_pass slavecommand in the
Restart the nut-client service
service nut-client restart
Update the system to start the service automatically
update-rc.d nut-client defaults
Fedora and CentOS versions 5 & 6
Fedora also stores the nut related data in
/etc/ups. Again here we need to perform the three steps we mentioned before, but this time we will need to start the upsmon daemon by hand. So to set up our fedora box as a network client:
Install the software using
yum install nut-client
MONITOR apc1200@asterisk 1 upsom_remote remote_pass slave
/etc/rc.d/rc.localto verify that the monitor program will start again after reboot.
Note: On my Fedora 20 system the file was not present so I had to create it, turn it into a shell script by adding
!/bin/shat the first line and make it executable.
[thanassis@skymnos ~]$ ps -ef | grep upsmon root 1898 1 0 17:37 ? 00:00:00 /usr/sbin/upsmon start nut 1900 1898 0 17:37 ? 00:00:00 /usr/sbin/upsmon start 500 2142 2118 0 17:38 pts/0 00:00:00 grep upsmon
A very good GUI based tool to help test the ups servers. It can be easily installed using the
package manager of your distribution -- just search for the
nut-monitor package and after you install and
run it, it looks like this:
Winnut is a Windows client, that runs as a 32bit service on Windows 7. The project has not been updated since February 24, 2011. I did install the software on a Windows machine but have not been able to do any serious testing. The program's configuration follows the same rules as the Linux clients. The only thing you have to is click the edit configuration file button
and then add the correct MONITOR Line in the
upsmon.conf file that will appear loaded into notepad. On 64bit systems you will also need to change the line
NOTIFYCMD "\"c:\\Program Files\\WinNUT\\alertPopup.exe\""
NOTIFYCMD "\"c:\\Program Files (x86)\\WinNUT\\alertPopup.exe\""