Tag: home automation

Corporate Expense Reduction: Energy

One of the things we’ve done with our home automation is tracking energy usage – partially because we want to size out a solar installation and the net metering in Ohio is awesome unless you produce more electricity in a rolling 12 month period than you use. So the installation has to be really close to your actual usage. But also because electricity costs money. Similar approaches may be beneficial to corporations. I’m using our 11 cent per kWh rate as an example. Actual rates depend on location and usage.

Does a company want to devote resources to “office automation” like we have home automation? Coupling motion detectors with smart outlets {or even just office schedules – if the last person is off shift at 7PM, dropping some device power at 8 should have no impact} to turn off power might save a lot in standby draw.

Even without home automation, companies can gather usage data to allow resources to be devoted to their biggest energy draws. The first step is identifying the big draws. We use Aeon Labs zwave clamp on home energy meters, but there are stand-alone energy meters. I’ve seen DIY Arduino based ones (https://olimex.wordpress.com/2015/09/29/energy-monitoring-with-arduino-and-current-clamp-sensor), or high end Fluke devices with clamps do the same thing (@5k+ for the Fluke … that’s a bit of an investment, but if someone’s got an energy metering capable fluke for other work ‘stuff’ … they may just need the 10$ clamps). Whatever equipment – clamp it on one circuit in a panel for a few days. Get a number, move it to the next circuit. Eventually you’ve got daily usage numbers for different circuits and just need to look at what is on those circuits to narrow down potential saving points.

We found obvious stuff – HVAC uses a lot of power. If a company leases a building with outdated equipment, use firm numbers in lease negotiation. The HVAC draws x kWh per year which costs us y $. A middle-road new system should draw z kWh which means we’re spending some concrete dollar figure per year because this system is so old. The same information can be used to cost-justify upgrades/replacements for company-owned buildings. Measure usage on lighting circuits. An office with old ballasts and florescent bulbs – what they are costing to run tells you if switching to LED {and there *are* LED T4/8 tubes that don’t require fixture replacements} makes any sense.

But we also found things I would never have even considered if I made a list of all of our non-trivial electrical draws. 20% of our annual electrical usage is the septic aerator (it literally uses more energy than the geothermal HVAC system in a year). We can get it down to 11% of our projected usage by cycling the thing on during even hours and off during odd (or on/off in twelve hour chunks, or 4 on / 4 off / 4 on / 4 off / 4 on / 4 off … new aerators have scheduling and do this themselves). Now that septic aerator savings is only like 250$ a year. Not a huge amount of money, but it’s 250$ I would never have realized we were spending otherwise.

From an IT perspective – if a server supports wake-on-lan … does a backup server and tape library need to be running 24×7? If someone kicks off a restore, can it be powered up (adds a minute, but saves power whenever restores aren’t running) and can it be programmatically powered on maybe half an hour before its backup jobs are scheduled to kick. Then power back down when no jobs report as running or scheduled for x hours. As a company, we mandate that all computers be left powered on so patches can be deployed overnight. What if the nightly patch check-in then powered the computer down (either because there are no patches or after installation in lieu of a reboot)?

Or a printer — there is no need for the printer to be in standby mode for the 15 hours a day no one is around to print. Or the weekends when no one is around. Or company holidays. One of the fairly large Xerox printers we have draws a continuous 11 Watts in sleep mode uses 71 kWh each year between 17:30 and 07:30 M-F and all day Saturday and Sunday. Maybe 72 kWh if you add company holidays. That’s not quite eight dollars a year in savings (and power consumption won’t be 0 if the device can be woken remotely) – but saving 6$ per printer in a company with 2000 printers is 12,000$ each year. Some of the older printers don’t even have a lower power sleep mode and draw 95 Watts in standby mode – 620 Watts per year when no one is around, and just under 70$ in electricity. Even better – HP offers an auto-off / auto-on on activity feature that allows energy to be saved during working hours.

Are there intangible benefits to energy saving initiatives? Get into the automation side of energy savings, would some tech magazine profiling the effort (free publicity, and tech magazines are a good place to advertise a company offering network services)? Can companies form partnerships with geothermal / solar / wind / whatever manufacturers to get cheap installations + publicity? Sadly, in some markets that may not play well (what, you don’t want to burn coal!?!) … but it might not be seen as a negative if it approached as a “save money, do right by stockholders AND customers” message instead of a “green, save the planet, global warming is bad” message.

Zoneminder Setup

I just installed ZoneMinder tonight. I don’t know if I missed a section in the documentation or something’s just missing — there’s doc for getting the build onto your box (or building your own from source). I didn’t want to install the package and all of its dependencies from their repo, so I manually installed the prereqs from the standard Fedora repositories. Installed the zoneminder rpm and switched from the ‘installation guide’ to the ‘user guide’. Which starts out on a web site. Umm … what web site? There’s definitely something missing here. Their package drops a config file in /etc/httpd/conf.d … *but* it presupposes that it is a dedicated server (which, in fairness, is the recommended configuration).

I edited the zoneminder.conf file and threw the whole thing in a VirtualHost tag, added an SSL cert for the hostname I’m using, and restarted Apache. OK, that’s better … I get *something*. Unfortunately ‘something’ is a massive MySQL error.

Some searching (rpm -ql zoneminder, then search through the files the package installed for something that looks good) yielded a config file at /etc/zm/zm.conf. Went in there, defined a database, user, and password. Created said database & user in mysql & assigned rights. Umm, stranger database error that leads me to believe the database hasn’t been initialized. Oops. LMGTFY. Found a SQL file at /usr/share/zoneminder/db/zm_create.sql and imported *that* … wasn’t sure if it was as simple as changing the zm database name in the SQL file to what I wanted or not, so I just used their default database name. Went back into MySQL and assigned the user I’d created earlier rights to the zm database and dropped *my* database. (Note, if you don’t use PHP date ‘stuff’, you may need to define the time zone in your php.ini file … I’d already set a default for other purposes).

Refresh and voila, I’ve got a system. You’ve got to click ‘start’ at the top for it to, well, start pulling in video feeds. I set up a VERY basic link to our WansView camera — ffmpg type, source is the full videostream.cgi URL, and remote method is “RTP/Unicast”. I can now see the video from our camera via the web site. WooHoo!

Now we need to get the motion detection set up & play with all of the options 🙂

Home Automation Lagering

We are about to make mead (we got near 30 pounds of local honey!). In researching mead-making, different yeasts have different alcohol tolerances … so you make a dry mead by using a yeast with an alcohol tolerance at or above the level your starting gravity would yield if it were fully fermented. A sweeter mead means you have a yeast whose tolerance is lower than that value … the greater the difference, the sweeter the mead. We are going to make a dry mead with Lalvin 71b-1122, a just slightly sweet mead by adding a little more honey but still using Lalvin 71b-1122, and a sweeter mead using Lalvin D-47.

71b-1122 has a very broad temperature range (59-86 F – and how cool is it that Google returns a yeast profile summary if you search for “71b-1122 temperature range”). D-47 is more particular — a published range of 59-68 F, but reading through homebrew sites has us wanting to stay around 63 degrees. Our sub-grade level is cool, but not that cool. Especially as fermentation warms up the fluid.

Scott is developing a home automation controlled fermentation “chamber”. The beer refrigerator is now plugged into a smart outlet. One of the Arduino kits we got has a temperature sensor. We can have a temperature probe monitoring the must and cycle the refrigerator’s power to keep it within a degree or two of our target.

Reverse Proxying WebSockets to An MQTT Server

If you are trying to reverse proxy OpenHab – that’s over here. This post is about maintaining your own private MQTT server and making it accessible through a reverse proxy.

We want to be able to update our presence automatically (without publishing our location information to the Internet). Scott found a program called OwnTracks that uses an MQTT server – and there’s an MQTT binding from OpenHab that should be able to read in the updates.

We didn’t want to publish our home automation server to the Internet, but we do want to send updates from the cellular data network when we leave home. To accomplish this, I set up a reverse proxy on our Apache server.

The first step is to get an MQTT server up and working — we Installed a mosquitto package from Fedora’s dnf repository

Once it is installed, create a directory for the persistence file & chown the folder to mosquitto uid

Generate a bunch of certs using the ot-tools (git clone https://github.com/owntracks/tools.git). I edited the generate-CA.sh file in the ot-tools/tools/TLS folder prior to running the script. It will more or less work as-is, but modifying the organisation names makes a cert with your name on it. Not that anyone will notice. Or care 🙂 Modifying the IPLIST and HOSTLIST, on the other hand, will get you a cert that actually matches your hostname — which isn’t a problem for something that doesn’t verify host name information, but saves trouble if you get your hostnames to match up.
IPLIST & HOSTLIST
CA_ORG and CA_DN

Then use generate-CA.sh to generate a CA cert & a server cert. Copy these files into /etc/mosquitto/

Edit the config (/etc/mosquitto/mosquitto.conf) – LMGTFY to find settings you want. Specify a location for the persistence file, password file, and add in the websockets listeners (& ssl certs for the secure one)
persistence_file /var/lib/mosquitto/mosquitto.db

password_file /etc/mosquitto/passwd

listener 9001
protocol websockets

listener 9002
protocol websockets
cafile /etc/mosquitto/ca.crt
certfile /etc/mosquitto/mosquittohost.rushworth.us.crt
keyfile /etc/mosquitto/mosquittohost.rushworth.us.key

Add some users
/usr/bin/mosquitto_passwd /etc/mosquitto/passwd WhateverUID

Start mosquitto
mosquitto -c /etc/mosquitto/mosquitto.conf

Monitor mosquitto for the owntracks ‘stuff’
mosquitto_sub -h mosquittohost.rushworth.us -p 1883 -v -t ‘owntracks/#’ -u WhateverUID -P PWDHereToo

Setting up the reverse proxy
The big sticking point I had was that the Apache WebSockets reverse proxy has a problem (https://bz.apache.org/bugzilla/show_bug.cgi?id=55320) which is marked as closed. Fedora has 2.4.23, so I expected it was sorted. However using tshark to capture the traffic showed that the relayed traffic is still being send as clear.

Downloaded the exact same rev from Apache’s web site and checked the mod_proxy_wstunnel.c file for the changes in the bug report and found they were indeed committed. In spite of the fact I *had* 2.4.23, I decided to build it and see if the mod_proxy_wstunnel.so was different.

Make sure you have all the devel libraries (openssl-devel for me … run the config line and it’ll tell you whatever else you need)

Get apr and apr-util from Apache & store to ./srclib then gunzip & untar them. Rename the version-specific folders to just apr and apr-util

Once you have everything, configure and make
./configure –prefix=/usr/local/apache –with-included-apr –enable-alias=shared –enable-authz_host=shared –enable-authz_user=shared –enable-deflate=shared –enable-negotiation=shared –enable-proxy=shared –enable-ssl=shared –enable-reqtimeout=shared –enable-status=shared –enable-auth_basic=shared –enable-dir=shared –enable-authn_file=shared –enable-autoindex=shared –enable-env=shared –enable-php5=shared –enable-authz_default=shared –enable-cgi=shared –enable-setenvif=shared –enable-authz_groupfile=shared –enable-mime=shared –enable-proxy_http=shared –enable-proxy_wstunnel=shared

Rename your mod_proxy_wstunnel.so to something like mod_proxy_wstunnel.so.bak and the grab mod_proxy_wstunnel.so that just got built.

Grab the CA public key & the server public and private keys that were generated earlier & place them whereever you store your SSL certs on your Apache server

Create a new site config for this reverse proxy – SSL doesn’t do host headers so you need a unique port. Clear text you can use a host header. Don’t forget to add listen’s to your httpd.conf and ssl.conf files!

ProxyRequests Off
<VirtualHost #.#.#.#:##>
ServerName mosquitto.rushworth.us
ServerAlias mosquitto
DocumentRoot “/var/www/vhtml/mosquitto”

SetEnv force-proxy-request-1.0 1
SetEnv proxy-nokeepalive 1
SetEnv proxy-initial-not-pooled
SetEnv proxy-initial-not-pooled 1

ProxyPreserveHost On
ProxyTimeOut    1800

ProxyPass               /       ws://mosquittohost.rushworth.us:9001/
ProxyPassReverse        /       ws://mosquittohost.rushworth.us:9001/
</VirtualHost>

<VirtualHost #.#.#.#:##>
ServerName mosquitto.rushworth.us
ServerAlias mosquitto
DocumentRoot “/var/www/vhtml/mosquitto”

SetEnv force-proxy-request-1.0 1
SetEnv proxy-nokeepalive 1
SetEnv proxy-initial-not-pooled
SetEnv proxy-initial-not-pooled 1

ProxyPreserveHost On
ProxyTimeOut    1800

SSLEngine On
SSLProxyEngine On
SSLProxyCheckPeerCN off
SSLProxyCheckPeerName off
SSLCertificateFile /etc/httpd/conf/ssl/mosquittohost.rushworth.us.crt        # These are the public and private key components
SSLCertificateKeyFile /etc/httpd/conf/ssl/mosquittohost.rushworth.us.key        #     generated from generate-CA.sh earlier.
SSLCertificateChainFile /etc/httpd/conf/ssl/ca.crt                # This is the public key of the CA generated by generate-CA.sh

ProxyPass               /       wss://mosquittohost.rushworth.us:9002/
ProxyPassReverse        /       wss://mosquittohost.rushworth.us:9002/
</VirtualHost>

Reload apache. Create a DNS hostname internally and externally to direct the hostname to your reverse proxy server.

Configure the client — generate a key for yourself & merge it into a p12 file (make sure your ca cert files are still in the directory – if you *moved* them into /etc/mosquitto … copy them back:
sh generate-CA.sh client lisa
openssl pkcs12 -export -in lisa.crt -inkey lisa.key -name “Lisa’s key” -out lisa.p12
You’ll need to supply a password for the p12 file.

Put the ca.crt (*public* key) file and your p12 file somewhere on your phone (or Google Drive).

Client config – Install Owntracks from Play Store
Preferences – Connection
Mode:    Private MQTT
Host:    hostname & port used in your **SSL** config. Select use WebSockets
Identification:    uid & password created above. Device ID is used as part of the MQTT path (i.e. my lisa device is /owntracks/userid/lisa). Tracker ID is within the data itself
Security:    Use TLS, CA certificate is the ca.crt created above. Client cert is the p12 file – you’ll need to enter the same password used to create the file

If it isn’t working, turn off TLS & change the port to your clear text port. This will allow you to isolate an SSL-specific problem or a more general service issue. Once you know everything is working, you can drop the clear text reverse proxy component.

Voila – reverse proxied WebSockets over to Mosquitto for OwnTracks.

Using BC And Command Substitution In OpenHAB’s Exec Binding

My husband has been setting up OpenHAB to control our home automation. Our dimmers are very direct – there’s a z-Wave binding that you set to 100 if you want it at 100%, set it to 18 if you want it at 18%, and so on. We have a handful of Zigbee bulbs, though, which are not so direct. We are controlling these bulbs through a Wink hub by running a curl command with the exec binding.

The OpenHAB exec binding runs a shell with a command string passed in from the -c parameter. Thus far, I have not found anything that runs within a shell not work in the exec binding. This includes command substitution {I personally use the backtick format instead of the $(command) format, but I expect the later to be equally functional}.

What is command substitution (without having to read the Open Group Base Specifications linked above)? If you run

kill `pidof java`

the shell takes the component within the backticks, evaluates it, and then takes the standard output and places that into the command. When “pidof java” returns “938 984 1038”, the command above becomes “kill 938 984 1038”.

We want to set the value to the OpenHab value (0-100) scaled to the Wink value (0-255 for GE Link bulbs) using command substitution with bc (an arbitrary precision calculator language). To evaluate a mathematical expression, echo the expression text and pipe it to bc. To set a bulb to 75% of its maximum brightness, our post data is “nodeId=a&attrId=aprontest -u -m9 -t2 -v`echo 2.55*75/1|bc`”.

Notice the divide by 1 at the end — that’s to turn a decimal value into an integer. If you use just 2.55*75, you post a value of 191.25 which throws an error. In bc’s language, / returns the quotient — this isn’t *rounding* but rather truncating the decimal portion( i.e. bc 9.99999/1 = 9).

We configure the OpenHAB item to take the selected value (the %2$s below), scale the value with bc, and insert the result into the curl command. We use a similar technique to read the data from Wink and present the scaled value through OpenHAB.

The item entry in our sitemap.items file:

Dimmer  DS_Pantry_Bulb_Level                                            “Bulb (Pantry Downstairs) [%d]”                                 <slider>        (gZigbeeBulb,gDS_Pantry,gLight)                                                                                 { exec=”<[/bin/sh@@-c@@echo `/usr/bin/curl \”http://wink.hub.address/set_dev_value.php\” -s -d \”nodeId=a&attrId=aprontest -l -m9;\”|grep Level|grep -oP \”\\d+\\D+\\K\\d+\\D+\\K\\d+\”` /2.55|bc:3600000:] >[*:/bin/sh@@-c@@/usr/bin/curl \”http://wink.hub.address/set_dev_value.php\” -s -d \”nodeId=a&attrId=aprontest -u -m9 -t2 -v`echo 2.55*%2$s/1|bc`;\”]”}

Parsing JSON In JavaScript

We’ve been trying to get our BloomSky data parsed and reflected in OpenHAB — we can automatically turn the lights on when there is motion *and* the luminescence is lower than some desired value.  Bloomsky has an API which allows us to retrieve JSON formatted data from our weather station. I never worked with JSON before – I’d heard the term, but didn’t actually know what it was … but I needed to parse it in a JavaScript transform. Does JavaScript do JSON? D’oh! Turns out JSON is an abbreviation for JavaScript Object Notation, and JavaScript parses JSON data really well.

Still need to turn my example web code into a transform that runs from OpenHAB, but getting values out of a JSON formatted string is as easy as using the “parse” function:

<html>
	  <head>
	    <script>
	      function parseMyData() {
		var input = '{"DeviceID":"83237E","LAT":41.226644299999997,"LON":-81.7224322,"ALT":292.78720092773438,"UTC":-4,"DST":1,"Searchable":true,"RegisterTime":1464494138,"CityName":"Hinckley","StreetName":"Bellus Road","FullAddress":"Bellus Road, Hinckley, Ohio, US","DeviceName":"Buzzard Cam 01","BoundedPoint":null,"NumOfFollowers":5,"Data":{"Temperature":80.528000000000006,"ImageURL":"http://storage.googleapis.com/bloomsky-img/eaB1rJytnZSmm5y3qJ1krJqwmJmtoJU=.jpg","Humidity":50,"Night":false,"ImageTS":1465938980,"Luminance":3445,"TS":1465938980,"Rain":false,"Pressure":29.087148500000001,"Voltage":2613,"UVIndex":"1"},"Point":{},"VideoList":["http://storage.googleapis.com/bloomsky-video/eaB1rJytnZSmm5y3_-4_2016-06-09.mp4","http://storage.googleapis.com/bloomsky-video/eaB1rJytnZSmm5y3_-4_2016-06-10.mp4","http://storage.googleapis.com/bloomsky-video/eaB1rJytnZSmm5y3_-4_2016-06-11.mp4","http://storage.googleapis.com/bloomsky-video/eaB1rJytnZSmm5y3_-4_2016-06-12.mp4","http://storage.googleapis.com/bloomsky-video/eaB1rJytnZSmm5y3_-4_2016-06-13.mp4"],"NumOfFavorites":0}'

		var jsonOfInput = JSON.parse(input);

		document.write("<P>Device ID is: " + jsonOfInput.DeviceID + "</P>");
		document.write("<P>Temp is: " + jsonOfInput.Data.Temperature + "</P>");
		document.write("<P>Luminance is: " + jsonOfInput.Data.Luminance + "</P>");
	      }
	    </script>
	  </head>
	  <body>
	  <h2>Press the button to start</h2>
	    <input type="button" onclick="parseMyData()" value="Parse"/>
	  </body>
	</html>