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Hobby Public Radio

Your ideas, projects, opinions - podcasted.

New episodes Monday through Friday.

Welcome to HPR the Community Podcast Network

We started producing shows as Today with a Techie 11 years, 6 months, 21 days ago. Our shows are produced by listeners like you and can be on any topic that "are of interest to hobbyists". If you listen to HPR then please consider contributing one show a year. If you record your show now it could be released in 14 days.

Latest Shows

hpr2278 :: Some supplementary Bash tips

Finishing off the subject of expansion in Bash (part 1)

Hosted by Dave Morriss on 2017-04-26 is flagged as Explicit and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: Bash Scripting | Comments (0)

Some supplementary Bash tips

Pathname expansion; part 1 of 2


As we saw in the last episode 2045 (and others in this sub-series) there are eight types of expansion applied to the command line in the following order:

  • Brace expansion (we looked at this subject in episode 1884)
  • Tilde expansion (seen in episode 1903)
  • Parameter and variable expansion (this was covered in episode 1648)
  • Command substitution (seen in episode 1903)
  • Arithmetic expansion (seen in episode 1951)
  • Process substitution (seen in episode 2045)
  • Word splitting (seen in episode 2045)
  • Pathname expansion (this episode and the next)

This is the last topic in the (sub-) series about expansion in Bash. However, when writing the notes for this episode it became apparent that there was too much to fit into a single HPR episode. Consequently I have made it into two.

In this episode we will look at simple pathname expansion and some of the ways in which its behaviour can be controlled. In the next episode we’ll finish by looking at extended pattern matching. Both are included in the “Manual Page Extracts” section at the end of the long notes.

Long Show Notes

I have written out a moderately long set of notes about this subject and these are available here.

hpr2277 :: Outernet and other projects

In this episode, I take a look at some different attempts to spread free internet access.

Hosted by m1rr0r5h4d35 on 2017-04-25 is flagged as Explicit and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (2)

hpr2276 :: Tunnels and Trolls and Dungeon Delvers

Klaatu talks about Tunnels & Trolls solo RPG series, and Dungeon Delvers

Hosted by klaatu on 2017-04-24 is flagged as Clean and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: Tabletop Gaming | Comments (0)

Klaatu reviews the solo RPG experience provided by Tunnels & Trolls community.

Additionally, he mentions a nice Creative Commons rulebook (if you can call 2 pages a book) called Dungeon Delvers.

hpr2275 :: Penguicon 2017

A look at the lineup for the 2017 event.

Hosted by Ahuka on 2017-04-21 is flagged as Clean and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: Penguicon | Comments (0)

Penguicon 2017 is a combined technology and science fiction convention in Southfield, Michigan, a suburb of Detroit, and presents over 500 hours of programming over the entire weekend. Of this, around 100 hours are open source, tech-related. In this episode I give you a look at the lineup you can expect to see.

hpr2274 :: First Microsoft Surface Pro Ubuntu 16.04 Dual boot

A short talk about converting a MS Surface pro from windows to unbuntu

Hosted by JWP on 2017-04-20 is flagged as Explicit and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (0)

Hi. I purchased the first MS Pro on ebay after hearing of a like project on the Linux Action Show. I do a lot of traveling and I am always feeling bad about not having a something with open source on it.

So one of the best for travel is the MS surface pro.

In short it works great with Ubuntu.

hpr2273 :: Fountain Pens

In this episode, I cover some of the basics of Fountain Pens

Hosted by m1rr0r5h4d35 on 2017-04-19 is flagged as Explicit and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (2)

For a good basic rundown of the parts of a fountain pen, The Goulet Pen Company has a fairly decent page at:

Fountain pens on Youtube:

hpr2272 :: In Which Our Hero Takes 4 Hours to Install Hyper-V Server 2012

A tale from the trenches. When good servers go bad.

Hosted by OnlyHalfTheTime on 2017-04-18 is flagged as Explicit and released under a CC-BY-SA license.
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So we had this server.

As all servers are wont to do, this one had run successfully for a number of years. Everything worked perfectly until it didn’t.

It ran, to my knowledge, only Hyper-V Server on its system drive, and had a second set of drives for hosting the VM that ran Microsoft Deployment Toolkit to service our depot. Our depot was on its own physical network, sharing with production only an ISP demarc.

I had long since abandoned the depot and its trappings, thinking it someone else’s domain, thinking my time better spent on client systems, thinking that I didn’t need to know what happened in the oft-ignored part of our operation. I assumed that it was set up properly since it had been so stable for so many years. But you know the old saying:

When you make assumptions you make an ass out of you and muptions.

The Problem.

Our monitoring systems reports the two depot servers offline, both the hypervisor and its virtual. I sent our depot technician to take a look. They come back online and he tells me that it needed to be rebooted. Having divested myself of giving a damn about the depot, I barely found the energy to shrug.

Then it happened again. I again sent the technician and promptly got wrapped up in some client-facing issue. I forgot about the servers until:

They went offline a third time. I didn’t have to tell my depot tech; he was watching the same feed as I. He rummaged a bit and came back with a story of defeat and virtual disks not being found.

“The server won’t boot because the Virtual disk can’t be found” he said.

“Ok, so you mean the virtual won’t come up, but what about the physical?” I replied.

“No, that’s what I mean. It won’t get past BIOS. It’s complaining of a virtual drive not being found.”

“Sounds bogus, let’s look.”

He was not wrong; that is what the screen said. And what it meant was RAID failure. I slid off the front of the server case and sure enough, one of the drives had popped.

Oh, did I mention? No backups.

The Rabbit Hole.

Drives pop sometimes, ain’t no thing. We build systems to be resilient. You slap a fresh one in there and it starts re-silvering and you get on with your day. Not this time, gentle reader.

While digging through the RAID controller, I found, to my amazement, horror, and utter confusion, that whatever chucklefuck set up this server put the two system drives in a RAID 0. As I stared at the screen and at the blinking amber drive light, all that could pass my lips was a quiet “Oh my god, why?”

In this scenario, I didn’t see any way forward, but through. So far, it had been demonstrated that the bad drive would behave for about 2 hours, then throw a fit. I shut down the server and took some time to think about how to proceed. In that time, I re-discovered some of the things the virtual machine was serving.

Things like: MDT, DNS, DHCP, PXE boot, but most importantly: the lone DC for depot.local (MDT needs a domain). Oh, and it was the only machine that was set up to manage the hypervisor through the Hyper-V console and Server Manager.


Compounding the issue, the virtual was not stored on the separate set of RAID 1 disks in this server as I had assumed. It was stored on the system drive. Oh joy, oh rapture.

My new mission: Rescue that virtual.

The Struggle.

First things first. I assume I’ll only have one chance to rescue this data before this drive bites the dust for good. I plug in the VGA and keyboard. Take a deep breath.

I turn on the server.

It fails to boot into the operating system. “Come on, you little shit.” Take out the drive and put it back in. Success. We boot into the OS and I’m presented with a log on screen. Password.

There are no logon servers available to process your request.

Shit, that’s right. The virtual is the only DC. K, local admin it is. Login successful. Presented with a command like and SConfig. Grab the terminal and start poking about. cd to C: and dir. Find a folder named VMs. Bingo. Started copying the VHDX to the RAID 1 set.

cp “C:\vms\Hyper-V Replica\Virtual hard disks\{guid}\{guid}.vhdx” E:\

The server moves the data at a respectful 700Mbps, considering its current degraded state. It eventually finished the transfer after about 10 agonizing minutes. Shut down the physical to preserve the bad drive.

We are out of the woods, but it’s still a long way to Gramma’s house.

The King is Dead; Long Live the King.

I have a plan. Now that I have the VHDX, and since we clearly need a replica server, I’ll push my luck. I’ll build a new server and see if I can replicate the virtual. I happen to have a disused server sitting right next to the bad server. It’s admittedly dissimilar hardware, but shouldn’t be a problem. I don’t know why it’s lying dormant or what it was used for in the days of yore, but it’s mine now. Eminent domain.

And here is the story of how it took me 4 hours to install an OS that usually takes 3 minutes.

We need to load up Hyper-V 2012 on this “new” server first.

As is standard practice, I disconnect all but one drive from the mobo. I do this because sometimes the Windows installer decides that the “SYSTEM” partition belongs on a different drive from the C partition and it makes me cry. I used rufus (what a fantastic little utility, really. I need to donate to that guy) to make a HV 2012 boot disk from ISO.

You know how it takes a few times to get a USB to go into it’s slot correctly? Not me. I whipped that bad mamma-jamma like a shuriken from 30 feet away and it slid perfectly into the front of the server. Fireworks, 100 doves, the works.

Boot it, get to the installer part where it asks you upon which drive you wish to install it. Boom, error:

Setup was unable to create a new system partition or locate an existing system partition.

Weird. Sounds like a problem with the disk, right? Open up diskpart, clean it, format, create partition, assign it a letter. No go. Try a different drive? Nope. Disconnect the cd drive maybe. No dice. Connect all the drives and try each one. Nada. Boot up into Ubuntu and use GParted to re-do what I did in diskpart. Zilch. Re-create the install media. Goose egg. Try the back USB ports. I’m running out of ways to say no, but in essence, nothing was making this error go away.

Screw it. Maybe this is why this server was sitting unused? Maybe it’s a bad mobo or something and frankly, I don’t care. Part out the drives and junk it.

We happen to have a literal pile of servers to pick from, so I grab the one on top because it’s the most similar to the bad server and because you must be out your damned mind if you think I’m digging through that mound of junk. This’ll do nicely.

Remember how I said I didn’t want to have anything to do with the depot? I still don’t. I want this new server to be unkillable, may he reign for a thousand generations. So, I may have gone a little overboard with the RAID setup for one simple hypervisor, which is going to be backed up and replicated.

That there is a 1TB RAID 1 with a hotspare and a 500ish GB RAID 5 with a hotspare. I never want to hear from this server again.

OK, so we start the Windows server install and:


No way. I have done this dozens of times, this is insane. I have used this exact same USB drive to do it! I can use it on an ancient spare laptop and go through the install perfectly fine. I have dug through pages of posts on forums and tried every last solution suggested except one. I find, on page 3 (!) of Google, someone say that it only failed for them when they used a USB 3.0 drive to install. I look at the end of my USB install media, see blue, then see red. NO. WAY.

So I hunt around for a USB 2.0 drive. Takes me a few minutes, but we had one holding up the leg of a table. Rufus took a bit longer this time. When the drive was cooked, I gingerly placed it in the receptacle and crossed my fingers. If this didn’t work, then I was all out of ideas. No clue.

It worked. I could not believe it. USB 3.0. Why, Windows, WHY?

Playing with Fire.

Creating a new domain is a pain in the ass. I considered a number of possibilities, but now that I had the re-install of this server figured out, I figured let’s go nuts and join the new hypervisor to the old domain depot.local. If you’ll remember from 6 years ago when I started telling you this story, the sole virtual server performed DCHP, DNS, and DC functions.

I powered up the bad physical server. It complained, but complied. Started the virtual, no issue. Waited a few minutes, then joined the shiny new server to the domain depot.local. From there, with the DC up and running it was a simple matter of using the Hyper-V console to set up replication. After about an hour of pacing back and forth like I was awaiting the birth of my first child, the virtual made it and was failed over successfully.

There were a few more issues to resolve, like the DNS server having the wrong IPs for just about everything even though they have been using statics for years, DHCP not responding on port 4011 for MDT for PXE Boot, DHCP being handed out by the virtual AND by the router on the same subnet (?!?!), and the DNS server refusing to connect over the HyperV vSwitch, but now at least I don’t have a knot in my stomach. I don’t know how this environment ever worked like this. What a mess to clean up.

I ripped the bad half of the RAID 0 out of the server like a man possessed. I nailed it to the wall behind my desk. There is a sign under it that reads: “RAID 0 is not RAID. If you use RAID 0 on anything, I will throw this hard drive at your head. I have good aim. It will probably hit your mouth.”

hpr2271 :: Raspberry Pi Zero W

an introduction to the new Pi Zero W from the Raspberry Pi Foundation

Hosted by Tony Hughes AKA TonyH1212 on 2017-04-17 is flagged as Clean and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: Hardware upgrades | Comments (1)

In this episode I talk about the new Raspberry Pi Zero W single board computer released on 28th February 2017 to coincide with the 5th Birthday of the Raspberry Pi Foundation.

This tiny 65x30mm single board PC has the following specs

  • 1GHz, single-core CPU
  • 512MB RAM
  • Mini HDMI and USB On-The-Go ports
  • Micro USB power
  • HAT-compatible 40-pin header
  • Composite video and reset headers
  • CSI camera connector
  • 802.11 b/g/n wireless LAN
  • Bluetooth 4.1
  • Bluetooth Low Energy (BLE)

Here are a couple of links to the foundation and a fuller review

hpr2270 :: Managing tags on HPR episodes - 3

Looking for the best way to store and manage tags in the HPR database, part 3

Hosted by Dave Morriss on 2017-04-14 is flagged as Explicit and released under a CC-BY-SA license.
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Managing tags on HPR episodes - 3


This is the third (and last) show looking at the subject of Managing Tags relating to HPR shows.

In the first show we looked at why we need tags, and examined the advantages and disadvantages of the present system of storage. We considered the drawbacks of this design when searching the tags.

Then in the second show we looked at a simple way of making a tags table and how to query it in order to fulfil the requirements defined in the first show.

In this show we’ll look at a more rigorous, efficient, “normalised” solution.

Long notes

I have written out a set of longer notes for this episode and these are available here.

hpr2269 :: Chocolate Milk

A sample show of the nixers podcast. Adam's story, milky chocolate, unicomp, and plan9

Hosted by venam on 2017-04-13 is flagged as Clean and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (3)

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