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I have to make a post mentioning the last couple of months, anything else would just be weird I feel. I hope you all are doing as well as can be in these unpredictable times. I know I have been personally affected by this pandemic in multiple ways yet I feel fortunate - things could have been so much worse. 
While I am one of the lucky people who work in a job that lends itself reasonably well to work from home, it took some time to get used to which had me focus more time and effort on things like home improvements and new daily routines to help me adjust to this new way of living.
Thankfully I was not alone in this journey and I am thankful to all my friends, family, and of course my partner for being there for me. We all need to take care of each other.
The last couple of weeks I have resumed my work on mainframe related projects and I have a series of blog posts that I wish to publish coming up. Some of these topics are going to be deep-waters territory for me, but the community has …
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Hacking update

Wow, time flies. In the past months I've been working on a handful of projects related to the mainframe, but nothing that is really finished - so I thought I would summarize some work I've been doing instead.

The fake FICON board - Fejkon

The latest project I've been working on is a custom card that will allow me to interface any mainframe using the FICON protocol. I have a lot of ideas on how this could help a lot of hobbyists out there, and possibly folks doing development for mainframes as well. For my own purposes, it would allow me to not be reliant on my (still broken) DS6800 array.

Fibre Channel research

The last couple of weeks I've been traveling for work, and I spent a long flight reading some publications I had saved up about mainframe and Fibre Channel. I will talk about some good sources of information later, but for now know that FICON runs over Fibre Channel, and indeed a lot of the reasons behind why Fibre Channel is known to be really reliable is that it more or less came out of IBMs requirements for accessing mainframe disk storage.
Enterprise disk storage has this annoying issue that the disk arrays are: HeavyPower-hungryRidiculously expensive An example: DS6800 is widely known to be an unreliable platform, and I would certainly never run a mainframe on it based on my experiences repairing mine. However it is as small as disk arrays get, but it is still 50 kg empty, and consumes 500W of power!
However the DS6800 is kind of a black sheep in reliability. What if we look at something bigger and better? The big brother DS8000 is known to be rock solid for example. The down…

Mainframe setup 1.0

A couple of weeks ago we streamed installing the mainframe in the datacenter from scratch. When we arrived the only thing that was there was the mainframe itself, some power cables, a fiber drop for Internet, and some shelves. Nothing was connected together.

Being a datacenter it is of course noisy from all the fans, so I am not surprised that streaming with sound did not work out. Never-the-less it seems like at least some folks enjoyed the stream.

Given that the stream content is somewhere around 12 hours, I figured a written walk-through of what we connected and why is in order. This is it.

The main connections you will need to your mainframe are:
Power Fibre Channel (FICON and/or FCP)Ethernet FiberEthernet Copper (Management) Power Power has already been covered in the Powering the mainframe article with the notable update that connecting both power cables for some reason trips the fuse in the datacenter. The manual says this:
Depending on the server configuration, this leakage cu…

Streaming setting up the mainframe

I want to try something I have never done before. I will stream setting up the mainframe.

Ok, let's try this. Stream for setting up the mainframe is going to be at I aim to start tomorrow (Sat) at 13:00 CEST / 11:00 Z. It's going to be recorded as well. Tune in and chat with me and my friend soundgoof when we install a mainframe from scratch. — Christian Svensson (@blueCmd) August 9, 2019 As I mentioned it will be recorded and I will post the uploaded videos here after the fact unless something catastrophic happens.

Update: The stream was successful! You can watch the recording here:

Powering a mainframe

The last few days have been eventful. I was contacted by the datacenter that the mainframe's cage is now ready for moving in, and the power has been made available. Very exciting! I grabbed my home-made power cables (more on that later) and my best screwdrivers and set off to the datacenter.

The datacenter staff, not needing a forklift in their day-to-day, had managed to solicit the services of a forklift, the associated operator, and some very handy folks to help navigate the mainframe from the storage space to its final location.

After some intense period of fighting the inclination of the road between the storage facility and the cage (and a door that was a bit too small) it was finally in place. Incidentally we were forced to trust the wheels on this pretty rough floor. I did not expect it to roll that well on raw concrete, I was pleasantly surprised. This thing is a tank!

Now, everybody wanted to see if it was working. My machine did not come with a power cable so I had to so…