## Thursday, 6 December 2018

### Customise Hue Bulb Startup Behaviour after a power cut

For years people have been wondering why and when Philips would allow users to customise startup behaviour after a power cut. No more! Philips has recently updated the firmware of the bridge and bulbs to allow for a custom power-on behaviour. Unfortunately for now it seems to allow only color temperature (whites) and brightness. But it’s better than nothing!

### Open the bridge debug page

• Open a browser (preferably on a PC or Mac)
• Go to https://discovery.meethue.com to see the IP address of your Hue bridge (it is called internalipaddress). In my case it is 192.168.1.32
• Open your favourite browser and enter http://192.168.1.32/debug/clip.html replacing my IP address with the IP you found in the previous step.

You should see the following page:

### Get an API key

If you don’t have an API key yet you can do the following:
• Replace the default value (/api/1234) with /api
• Paste the following content in the ‘message body’ field: {"devicetype": "debug_credential" }
• Press the ‘POST’-button on the web page
• Run to your Hue Bridge and press the round button on it
• Press the ‘POST’-button on the web page again
• Copy the value for “username” to some text editor so you won’t lose it. This value represents your API key.

### Identify the lights to modify

In the URL field of the debug page you can append your username, for example /api/0123456789012345678901234567 if your api key is 0123456789012345678901234567.

Next you can get a list of lights by appending /lights to the URL. Then you can press the GET button.

Every light that allows custom startup behaviour will have a startup key in the config property (see image below).

Write down all the ID’s of the lights that you want to modify and that allow custom startup behaviour.

 Example showing that the light with ID 1 allows custom startup configuration. You can also see 2, which shows the ID of the second light in the response.

### Modify the lights

Append the ID of the light you want to customise to the URL. As a sanity check, press the GET-button and verify that you get the status of the light in the response (no errors).

Paste the following in the Message Body field:
{
"config": {
"startup": {
"mode": "custom",
"customsettings": {
"bri": 254,
"ct": 500
}
}
}
}

• Adjust the Bri (Brightness, 0-255) and CT (Colour Temperature, ranging from 153 (6500 Kelvin, bright white) to 500 (2000 Kelvin, warm white).
• Press the PUT button
• Repeat for the other lights
Now to verify that it works, turn off the physical power switch to your light, wait for approx 5 seconds, and flip the switch again. Enjoy!

## Sunday, 16 July 2017

### HP Microserver Gen8 + i3 2120: does it ECC?

So the interwebs does a lot of claims about whether the Sandy Bridge generation i3's support ECC memory. For example here, here and here. Intel ARK does not show any information that mentions ECC support for the i3-2120.

Now as some of you have read, I've purchased an HP Microserver Gen8 with a Celeron G1610T inside which does support ECC. I purchased a second-hand Intel Core i3-2120 but as soon as it arrived my colleague said "well that's lame, it doesn't support ECC". I researched the internet and came to a sad conclusion. There seemed to be no official support for ECC. Why risk ruining a "production" server with a non-ECC capable CPU? So the CPU disappeared in my desk.

### A few months later

I re-did some of my research and realised that HP did offer the Microserver with i3 processors from the Sandy Bridge generation. This meant that the hardware should be capable and knowing that most of the cpu's from a certain family probably are from the same wafers it wouldn't be too far fetched to assume that most (if not: all) of the chips from the same series should be able to support ECC.

### Long story short

I'm running the i3-2120 now in the Microserver Gen8 and it works perfectly. ECC is shown as enabled in both the iLO and unRaid. No issues whatsoever. An i3 CPU of this generation can be found second hand between 25 and 45 euro's (approx.). And don't worry about the TDP except if you're hammering the system 24/7. My temperatures haven't gone up at all :). So I can recommend this upgrade to anyone wanting to get some more oomph from their Microserver Gen8 with a G1610T in it (which is a great deal on it's own!).

## Sunday, 20 November 2016

### LEDE project: prevent having to re-flash the latest nightly build every time you need a new package

I really admire the LEDE project and the reasons why they decided that it was necessary to fork openwrt and continue in a way that they saw fit. Unfortunately as they only recently started (somewhere about May 2016) there are no official releases yet and this means that there are only nightly builds.

This 'guide' will work for both openwrt and lede nightly builds. The reason is that every night the packages and dependencies get rebuilt and packages that rely on a specific kernel/kernel module version can not be installed at a later moment (when the new nightly build replaces the previous one online). To solve this we can make a copy of all packages for a given nightly build. In a nutshell:

2. Run the commands that download all packages from the LEDE/openwrt site
4. Run a local webserver
5. Modify the package repository URL's to match your local webserver

So lets get started!

This is easy and probably something you've done before. If not: check out the architecture of your router and try to find whether openwrt/LEDE already supports your router. If they don't you're out of luck for now. For this guide I'll be using the TP-Link Archer C7 which is contained in the ar71xx builds of both LEDE and openwrt.

### Run these commands that download all packages from the LEDE/openwrt site

The commands above should download all the packages that LEDE references within it's "software distribution feeds". For openwrt all references to lede-project.org should be replaced with openwrt.org. If you already have a version of openwrt/LEDE installed you can just make sure that you wget every of the URL's in the list instead of the URL's I provided above. Checkout 'System > Software' => Configuration tab for a list of feeds used by the current firmware.

After downloading the feeds you might want to move the contents of the downloads.lede-project.org/snapshots folder to a new folder. I'm using /Users/flix/Documens/lede-snapshots here as the /Users folder can be shared with Docker containers by default if you're using macOS. Not sure about how permissive Linux is in this regard.

After downloading the packages you can install the firmware. To be sure that your 'offline' package feeds actually will work I suggest not (re)installing any of your packages just yet. Just the firmware.

### Run a local webserver

Of course, the goal of downloading the packages is to serve them at a later moment in time. Let's get it started:

docker run --name nginx -v /Users/flix/Documents/lede-snapshots:/usr/share/nginx/html:ro -d -p 8080:80 nginx

The above command will pull an nginx container from docker hub and tell it to serve your local folder (containing the packages) on port 8080 from the machine you're running on. Of course you can copy the files to your home server, NAS, raspberry pi or any other device that can run a web server permanently, but for my use case (occasional desire to try out a package) I find spinning up a docker container the easiest.

### Modify the package feed URLs

So now we can just swap the downloads.lede-project.org/snapshots part with the IP address of our webserver. This is it! You can now install packages from your local package mirror! Good luck!

## Monday, 7 November 2016

### The HP Microserver Gen8 for EUR 200. Is it worth it?

So recently our Drobo at QwikSense (my other company) died. Which wasn't really a problem, except that it was storing our Time Machine backups for my computer and my colleagues' MacBooks. So I was looking for a reliable storage solution with room to spare for an extra disk and preferably with ECC memory.

In the NAS world you're either out of luck if you're looking for something at around €200. Most of the time this will give you an ARM device with HDD-slots. On top of that this locks you into the vendor firmware (and support) and most of the time building something yourself with the provided kernel/firmware sources is not enough to build a robust solution that gives you a 'simple' user interface that just does what it should.

Of course we could build something ourselves. Whack a Mini-ITX board in a dito casing and voilà: hard disks attached to your network. But I don't have the time to do this and the number of Mini-ITX boards that sports an ECC-capable CPU/RAM at a reasonable price is close to zero.

### Our saviour

Enter the HP Gen8 Microserver. The model with a Celeron G1610T and 4GB ECC(!) RAM can currently be purchased in the Netherlands for €203 euros at the cheapest reliable internet store at the time of writing! Now the strange (and awesome) thing about this tiny server is that it has a CPU, memory and a motherboard that support ECC! Can you believe it? And as an extra, HP's ILO4 management solution is also present. You can actually turn this thing on remotely if it's switched off. You can forcefully reboot it if the kernel crashes. It has features that "real" servers have, but in a tiny and silent package that looks AWESOME.

Note that the image above was ripped from 3dnews.ru. Also note that this is not the exact same model that you can get for such a low price. My model did not come with an optical drive, but who needs that anyway?

### Current setup

We still had some drives from the Drobo, so we put those in and added a 128GB SSD from Plextor to act as a caching drive. This confirmed my suspicion that the Drobo was in fact dead as a dodo. The drives were all okay! Because some of the drives that were used in the Drobo were WD Greens (and everybody is always crying about how WD Greens drop out of RAID arrays) I decided to WDIDLE3 them. The easiest way for me was to get UBCD, put it on a USB drive and boot the Microserver from that. Now I must stress that you should NOT connect ANY other drives than the ONE drive you want to flash (except for USB disks of course, they don't count). When booting from de USB drive, open "Disk Management" or something similar (sorry, I forgot what it actually was) and then select WDIDLE3 at the bottom of the list of tools. You might get a list with a lot of choices and a countdown. Let the countdown pass and wait for a DOS-like prompt. At the prompt enter the following command:

WDIDLE3.exe /s300 (for 5 minutes).

That's it. Power down the system and repeat for any WD Green drives you have lying around. Unraid time!

### Unraid

Since I saw LinusTechTips' 7 Gamers 1 CPU build I was very interested in unRaid as a storage solution. While I'm still running my Netgear ReadyNAS 4 Ultra at home (running ReadyNAS OS6 while Netgear only provided updates on OS4) I have wanted to own a machine like this. Docker on the ReadyNAS wouldn't work (because I believe the kernel was too old, not sure if that is still the case since they migrated to Jessie in the latest firmware update) but on unRaid the sky is the limit as VM's, Docker and plugins can all be used out of the box. There is a very active community providing solutions to run Plex Media Server, Resilio Sync, CouchPotato, SabNZBD and many more tools for media management. As we use Resilio Sync at work I decided to install that.

Note that the basic license for unRaid allows a maximum of 6 internal drives (== SATA) while the MicroServer only has 5 SATA ports (the fifth port is for the optical drive). The USB drive does not count towards the number of drives. Unless you're planning on adding a SAS card and an external storage enclosure you'll be fine with a basic license. And if you're not, you probably weren't planning on keeping the budget low anyway.

 Photo from a review on tweakers.net(dutch)

### Power consumption

While I've read different thing about the Gen8 Micro I've not been able to measure the power consumption yet. Hopefully I'll be able to report on that soon.

### Upgrades (and potential for win)

The Gen8 Microserver has a regular desktop-formfactor Intel CPU on board in socket 1155. While the CPU has a TDP of just 35 watts, many people have retrofitted their Gen8 with beefier CPU's. This is one of the cheapest ways to create a powerful, compact and mostly silent reliable server for a small company or for media streaming. Especially if you have a few drives lying around, this project (including CPU upgrade, SSD cache disk and unRaid license but excluding HDD's) would set you back around €420. Sounds like a sweet deal to me! But even without the CPU upgrade it's a great deal. Let me know what you think!

## Sunday, 21 August 2016

### Energy measurement with Domoticz and Grafana. Yes, it's easy!

A while ago I started tracking the power and gas consumption at home. To do this I read the meters every sunday afternoon and this gave me some insight in the power consumption. Unfortunately this also means that you have the measurement resolution of a week, so you can't really change your habits and see the effect on power/gas consumption.

## Sunday, 14 August 2016

### 11 Months Later: About productivity and mental health as a software dev

Recently I was asked whether I could share the tips and tricks that I still implement from my post from about 11 months ago. At first, I wasn't even sure that I would be able to name things I've learned and managed to keep doing.

Then I started thinking: is it even important that I can name them? Do I have to be consciously aware of the improvements I've made? But maybe the more important thing to realise is: even if I gain a single improvement from reading a book, something tiny that I did not do before, it is a gain and it is worth it! On top of that, everyones situation is different. This is why the stuff that helped me might not necessarily work for you.

So in my opinion books like these should be used more like frameworks, toolboxes, but not as a manual or bible. Similar to how this post describes the concept of Scrum implementation:
The Scrum framework leaves different options and tactics to play the game, ways that are at any time adopted to the context and circumstances.
Even if you implement only a small subset of the possibilities that Scrum provides, you're still benefiting from it and you can choose to combine it with other tools within (or even outside) the Scrum framework to streamline (optimise, improve, whatever) your work(flow) even more. This is something that is explained based on examples and anecdotes in the book Scrum & XP from the trenches, which you can download for free!

#### In conclusion

While I don't want to sum up the things I do better because they might not work for you, I'll list the things I currently do and things that I wish I would be better at implementing. These are from Blueprint of a productive programmer as the other book (Becoming a better programmer) is basically a huge list of great advice that you should probably read every 4 weeks until you really think you're implementing > 10% of it :).

Things I have learned and am able to implement (at least partially):

• Chapter 2 from Blueprint of a productive programmer:
• Minimise Distractions, Stay off Facebook (I actually uninstalled FB and WhatsApp from my phone)
• Avoid meetings (unless it's REALLY clear what needs to be discussed for both parties and other means of communication will NOT suffice)
• Commit to repository often (especially if you have trouble focussing because of stuff like A.D.D.)
Stuff that I really want to do better (but have forgotten to actually keep doing)
• Chapter 5 from Blueprint of a productive programmer:
• Eat the right food
• Take regular breaks
• Prevent or treat RSI
At the same time I found the book as a whole to give me a great insight in overall pitfalls in your daily routines as a programmer. If you're a programmer (and even if you're a pretty good programmer) I'm sure you will gain something from reading it :). Again, here are the books:

Amazon ebook

## Monday, 8 August 2016

### Tidying up the "server room"

I have a NAS, a UPS, a Powerline adapter, a Philips Hue Bridge, an OpenTherm Gateway, and an OpenPi (Raspberry Pi Compute Module breakout board) in the hallway closet. There also was a 2nd gen Airport Extreme, but it has been replaced with a less power-hungry and more performant alternative. But even then, it was an utter mess.

Unfortunately I have forgotten to make a 'before' picture, but I assure you, the empty space next to the NAS was filled with the items listed above. Wires everywhere. And even removing the Airport did not solve this.

Then I decided, everything with mounting holes has to hang on the wall. And sometimes it's these small things that make a big difference. Mounting a piece of wood to the wall and putting some screws in allowed me to reduce the cable clutter (most of the cables can now be tucked away behind the NAS) and because the devices aren't laying all across the place, power cables are now routed together in a bundle.

Now the only thing I have to do is wall mount the OpenPi. But I'll do that some other day. Even small improvements like this can make a great difference: it's so much easier to service a device without accidentally unplugging something else! Do yourself a favour and go after the low hanging fruit. You'll thank yourself later :)