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Server Outage: Warren the Hero

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Dirty MotherboardDirty MotherboardI doubt many people actually noticed but the server that runs this site (and about a dozen more) and my email... died sometime between 4:30 and 6:40 this morning. I texted (using Google Voice since I do NOT own/want a cell phone) Warren (since the server is in his house) about 6:38 and he responding back at 7:10 saying the server was dead. It would power on for about a second and then immediately turn off. It was full of dust bunnies so Warren cleaned it out and re-seated everything that might have had a loose connection... but still power-on failure. Warren opened up the power supply and cleaned it out. Inspecting both the motherboard and the power supply, there were no obviously bad components... no bad caps. Still no results.

Without a quick fix we decided to try to get a temporary system going... perhaps using a desktop computer with 4 SATA ports. 4 SATA ports are needed because the dead server has 4 hard drives that are in a Linux software RAID 5 configuration. Luckily Warren had access to a spare Dell OptiPlex 960 Core 2 Duo system with 8GB of RAM and 4 SATA ports. Many tower systems that have 2 hard drive bays come with 4 SATA ports so they can support 2 HDs and 2 optical drives. Getting the cables to go where they needed to go (both data and power) for loose drives seemed to work and for the time being the desktop power supply seems to be beefy enough to run all of the drives. Seeing as we run CentOS 6.x for OpenVZ... I was concerned that the network chipset would be too new... and for a little while that seemed to be the case... but Warren booted from a CentOS 6.7 LiveDVD and the network worked fine... so we knew it was a configuration issue from the previous hardware configuration. Turns out the NIC was detected as eth2 rather than eth0. While that could probably have been resolved by nuking a udev rule file somewhere, Warren just moved and edited the eth0 config file so it was eth2 and we were up and running again.

Dirty Power SupplyDirty Power SupplyWhile I do have backups (a couple of days old) and have previously researched a few cloud services (6sync and fastmail are on my radar) just in case, it is great to be back up after a few hours rather than having to worry about transferring a few hundred gigabytes of data before we are back up.

For the mid to long-term we haven't thought about where to go... and are just happy to be up and running again. Warren had it back up about 2 PM so he put a good 7 hours in today. Turns out Warren starts the Montanan Marathon early tomorrow morning, which he has been training all year for, so he wanted to get some rest today. I hope he does get some rest after saving our hobby server. Thanks Warren! I hope you do well in the run tomorrow buddy.

Video: Blender's new short film and ffmpeg vp9 test

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About a month ago the Blender folks released a new film project named Cosmos Laundromat.

Two days ago the ffmpeg folks released version 2.8. I saw one of the changes was that for webm they are now defaulting to using the vp9 video codec and the opus audio codec. Previous releases defaulted to webm with vp8 and ogg.

I've been following vp9 for a few years now... and every once in a while I'd try the libvpx tools and ffmpeg's support for vp9... but it was never quite there yet for non-experts (me). With this release, I say that vp9 is very, very close to viable. The only problem is that the encoding speed still leaves a lot to be desired. For the best results, two pass encoding is required. Using a number of 1080p video sources in h.264 format (all of the Blender films downloaded from YouTube) and a contemporary Intel i7 CPU, I get a little over 100 Frames Per Second (FPS) on pass 1 and between 7 - 9 FPS on pass 2. With a video that is ~24 FPS (all my source videos) it takes a little over 3x realtime to encode them. Well, more because of the two passes. The more popular codecs in ffmpeg are better than real time including vp8/ogg-based webm. Of course those numbers are all highly variable depending on the source material and the hardware you run it on... but you get the idea.

Ok, so encoding speed isn't so great. I'm sure that will get better over time. I'd expect it to be cut in half sometime over the next couple of years... if we are lucky... that and faster hardware... and perhaps GPU encoding support in newer hardware.

But anyway, enough about the encoding speed, how is the quality? Well, see for yourself. I think it truly lives up to the 1/2 the filesize for the same quality compared to vp8/ogg or h.264. I embed Cosmos Laundromat above then directly link to additional ones below if you want more. vp9/opus webm files should play in contemporary versions of Firefox, Google Chrome, Microsoft IE if you have some plugin installed (haven't tried it) and supposedly coming soon to Microsoft's Edge browser in Windows 10. Safari? Probably never. Play in your browser or right-click download and play with your preferred media player.

Don't blame any download / playback retrieval slowness on vp9... it's probably a lack of bandwidth on the server side... so be patient and pause it until some is buffered. Moving around the playhead should work fairly well unless bandwidth is an issue.

Full screen that if you want. Doesn't that look great? It's 720 x 302 resolution with 400 kbit video and 96 kbit audio. That's why all of the files have 496k in the name. So that's like 62KB / second transfer. Pretty good quality huh?

More vp9 re-encodes with ffmepg 2.8:

2006-Elephants_Dream-496k.webm (38.4MB, 10:53)
2008-Big_Buck_Bunny-496k.webm (31.8 MB, 9:56)
2010-Sintel-496k.webm (52.9 MB, 14:48)
2012-Tears_of_Steel-496k.webm (43.3 MB, 12:14)
2013-Caminandes-Gran_Dillama-496k.webm (8.7 MB, 2:26)

Want to know how it works on Hollywood / live action movies? Here's the trailer for the upcoming film, "The Martian". I don't think I'll get into any trouble for posting a trailer, right? Again, 720 x 405 @ 496 kbit. The black bars were in the original and I didn't remove them.

2015-The_Martian-Trailer-496k.webm (11.5 MB, 3:17)

Want to give vp9 a try? I doubt many distros have packages for ffmpeg 2.8 yet but you can download the static .tar.xz from ffmpeg's site and run it on most Linux distros. That's what I did. I'll leave finding the URL up to the reader because it will certainly change.

So far as encoding goes, I didn't do anything fancy. Just something like:

ffmpeg28 -y -i source.mp4 -f webm -vf scale=720:-1 -b:v 400k -an -pass 1 output.webm.pass1 ;
ffmpeg28 -y -i source.mp4 -f webm -vf scale=720:-1 -b:v 400k -b:a 96k -pass 2 output.webm

I took the static ffmpeg binary and plopped it in ~/bin/ffmpeg28 so I could easily tell it apart from the stock ffmpeg binary. Enjoy!

Video: The Mystery of Dan Walsh

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Everyone knows Red Hat's Dan Walsh as the SELinux guy... and more recently as the guy who pronounces Docker in a Boston accent as "Dockah". Turns out he was the subject of a recent TNT Network's Rizzoli and Isles episode. Enjoy. Oh, and, "All roads lead... to Dan Walsh." (the missing last 3 seconds)

For those with iFrame issues, here's the direct link: dan-walsh-mystery.webm

Video: Linus Torvalds - Why You Should Choose A Career in Linux

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Just noticed this short video and I thought it might interest some. I already have a "career in Linux" myself. How about you?

Video: The Next Big Little Thing, C.H.I.P.

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I ran across this video today. I know there is a lot of fever over the $9 C.H.I.P. but I found it very interesting listening to one of the C.H.I.P. guy talk about the challenge and the rewards of such a project. Enjoy!

Video: LibreOffice - Online and the Cloud

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Ever experienced a presentation by Michael Meeks? He reminds me of Monty Python... but I digress. Michael is a well known LibreOffice person and here is a recent talk (published June 26, 2015) from him for, I assume, the Swish Open Source User Group.

I decided today would be a good day to post this because LibreOffice 5 was released. Enjoy!

The Facebook Shirt

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While at LinuxFest Northwest 2015 I got my hands on a nice black fedora t-shirt. I've been wearing the t-shirt for a while now and have come to the conclusion that the "f" logo, logo colors, combined with the use of the word "friends" printed around the logo equates to poor marketing. There are other obvious words such as freedom which any good Linux fan boy or girl would zero in on. But as a general rule, most folks want to know why I am wearing a Facebook t-shirt. That response is pretty universal. They see the color and the letter "f" as well as the design of the letter and instantly equate the "f" to Facebook. Some even consider the printing of the word "friends" to be further proof that the t-shirt is really a Facebook t-shirt.


Video: Plasma Mobile

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While it might be a while before this becomes complete and compatible enough to run on your own mobile device, it sure looks good to this Plasma 5 desktop user. Enjoy.

For those who might be iFrame impaired, here is the direct YouTube link: https://www.youtube.com/watch?v=auuQA0Q8qpM

Video: Super Privileged Containers

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For anyone who hasn't seen this yet who is interested in containers, this is a must see. Watch Red Hat's SELinux guru Dan Walsh explain and demo Super Privileged Containers from the Red Hat Summit 2015. Enjoy!

For those who are iFrame challenged, here's the direct YouTube link: https://www.youtube.com/watch?v=dM2Fc53Dtd4

Video: systemd at the Core of the OS

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Oh look... another presentation by Lennart on systemd... this one from the CoreOS Fest 2015. Enjoy!

For those who are iFrame challenged, here's the YouTube link: https://www.youtube.com/watch?v=VIPonFvPlAs

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