4 Generate graphs for temperature and humidity by utilizing Munin.
9 0. Keep a logfile with the most recent single line
10 1. Use the munin plugin to generate munin-compatible data from the log file
15 0. Checkout the munin plugin code:
17 $ git clone git://git.cweiske.de/usb-wde1-tools.git
20 1. A process needs to watch the USB interface and log the last
21 line with temperature data into a log file.
22 You can do that manually with
23 $ socat /dev/ttyUSB0,b9600 STDOUT |./munin/log-single-line.sh test.log
25 The most easy way is to run
26 $ cd munin && nohup ./usb-wde1-log-last.sh &
27 once. It backgrounds the logging process and logs into /tmp/usb-wde1-last.
28 This process needs to be started whenever the machine is rebooted.
30 2. Link the munin plugin:
31 $ cd /etc/munin/plugins
32 $ ln -s /usr/local/src/usb-wde1-tools/munin/usb-wde1_ usb-wde1_temperature
33 $ ln -s /usr/local/src/usb-wde1-tools/munin/usb-wde1_ usb-wde1_humidity
35 3. Configure the plugins
36 Edit /etc/munin/plugin-conf.d/munin-node and add the following lines:
38 env.logfile /tmp/usb-wde1-last
41 env.sensor0 Living room
46 $ munin-run usb-wde1_temperature autoconf
48 $ munin-run usb-wde1_temperature config
49 - should display the plugin configuration with all environment variables
51 $ munin-run usb-wde1_temperature
52 $ munin-run usb-wde1_humidity
53 - should display the current values from the log file
55 5. You are done - enjoy.
59 Debugging & Development
60 =======================
61 The dummy data generator is a small php script that generates log lines
62 as they would come from the usb-wde1 usb port:
63 $ ./dummy-data-generator.php |./munin/log-single-line.sh test.log
65 Local (non-installed) plugin setup:
67 $ ln -s usb-wde1_ usb-wde1_temperature
68 $ ln -s usb-wde1_ usb-wde1_humidity
72 Running the munin plugin for development purposes is also relatively easy
73 since you can pass the environment configuration variables
74 from the munin configuration on the command line:
75 $ logfile=test.log sensors="0 1 7" ./munin/usb-wde1_temperature
77 When you have problems running the munin plugin, try to
86 cu: open (/dev/ttyUSB0): Permission denied
87 cu: /dev/ttyUSB0: Line in use
89 Only way that I found to fix this was change ownership of `/dev/ttyUSB0` to uucp::
91 $ chown uucp /dev/ttyUSB0
94 HTML/Plain text output
95 ======================
96 You may use ``htmlreport/gen-html.php`` to generate HTML or plain text
97 files with the temperature and humidity information.
99 Install PHP and the PHP rrd extension (``pear install pecl/rrd``) to make it
102 Run ``gen-html.php`` every 5 minutes.