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Brocade Fabric OS downloads

Fabric OS is what runs on the SAN switches I will be using for the mainframe. It has a bit of annoying upgrade path as the guldmyr blog can attest to. TL;DR is that you need to do minor upgrades (6.3 -> 6.4 -> 7.0 -> ... > 7.4) which requires you to get all Fabric OS images for those versions. Not always easy.

So, let's make it a bit easier. Hopefully this will not end up with the links being taken down, but at least it helped somebody I hope.

These downloads worked for me and are hash-verified when I could find a hash to verify against. Use at your own risk etc.

The URLs are:…
Recent posts

Unboxing accessories and DS6800 troubles

I am back in Switzerland. It has been a good two months away from work, and the first morning after coming back I rushed to the office to unpack and inspect the goods that will hopefully make the mainframe come alive.
So far the equipment is: DLm2000 virtual tape system1x Virtual Tape Engine (VTE)1x Access Control Point (ACP)2x Brocade 5100 SAN switch1x Arista DCS 7050S-64-R 10/40 Gbps switch I am also eagerly awaiting 2x Brocade 7800 SAN switch which should help me connect with other mainframers in the world and share some storage with them.
The Arista and the Brocade 5100 were really no surprises, booted up fine and had decently recent firmware. No worries there, so I'll skip the details. DLm2000 The DLm2000 is a component I am excited about and I think has great hack potential. It is more or less 2x FICON PCIe cards, and 1x 10 Gbit/s card. It presents itself as one or multiple tape drives and stores the drives as AWS tape files. Given the size of the server itself (2U + 1U) and …

Mainframe project news

This is going to be a short update to share some good developments in the project.

First of all: the mainframe has cleared customs and has been received by the datacenter. Customs caused a bit of a headache as eBay lists the sale price as the "Buy it now" price even if an agreement was put in place. This is usually fine as they values do not diverge a lot but in this case it was $300,000 vs $12,000 which would mean a significant difference in taxes to be paid. Thankfully the customs department listened to my arguments and they agreed that the accepted offer is what I should be taxed on. I must say that I am very pleased in the help UPS provided me with here, I assumed all logistics companies had gone sour but UPS redeemed themselves in my eyes with this delivery.

The next issue was that the datacenter told me they discovered the mainframe would not fit the elevator they had to take for the spot they had planned for. They are still processing alternatives, but I am not too wo…

Why have mainframes as a hobby?

My earlier blog article named Buying an IBM mainframe did get way more exposure than I could have hoped for, thanks to everyone that read it! The discussions on various forums did naturally evoke some interesting questions. Mostly they are "Why?" in various shapes or forms. It is a totally understandable reaction, and thus I want to present some of the things that I am excited about having mainframes as a hobby.

I present to you: the follow up questions on the statement "I bought an IBM mainframe".
Why? I thought mainframes were dead First of all, they are not. If you are buying a new mainframe today you will get a beast in terms of performance and especially I/O capability. There is no server platform that compare to my knowledge in pure numbers if you do not include cost. Of course, you would care deeply about cost in any real-life situation but the point is to dispel the notion that mainframes are antiquated technology wise.
Even my 8 year old z114 can run with …

System z on contemporary zLinux

IBM System z supports a handful of operating systems; z/VM, z/VSE, z/OS, z/TPF, and finally zLinux. All the earlier mentioned OSes are proprietary except for zLinux which is simply Linux with a fancy z in the name. zLinux is the term used to describe a Linux distribution compiled for S390 (31 bit) or S390X (64 bit). As we are talking about modern mainframes I will not be discussing S390, only S390X.

There is a comfortable amount of distributions that support S390X - more or less all of the popular distributions do. In this list we find distributions like Debian, Ubuntu, Gentoo, Fedora, and RHEL. Noticeably Arch is missing but then again they only have an official port for x86-64.

This is great - this means that we could download the latest Ubuntu, boot the DVD, and be up and running in no time, right? Well, sadly no. The devil is, as always, in the details. When compiling high level code like C/C++/Go the compiler needs to select an instruction set to use for the compiled binary. Eve…

Buying an IBM Mainframe

I bought an IBM mainframe for personal use. I am doing this for learning and figuring out how it works. If you are curious about what goes into this process, I hope this post will interest you.

I am not the first one by far to do something like this. There are some people on the internet that I know have their own personal mainframes, and I have drawn inspiration from each and every one of them. You should follow them if you are interested in these things:
@connorkrukosky@sebastian_wind@faultywarrior@kevinbowling1 This post is about buying an IBM z114 mainframe (picture 1) but should translate well to any of the IBM mainframes from z9 to z14.

What to expect of the process Buying a mainframe takes time. I never spent so much time on a purchase before. In fact - I purchased my first apartment with probably less planning and research. Compared to buying an apartment you have no guard rails. You are left to your own devices to ensure the state of whatever thing you are buying as it likely…

How-to: Dump all disks on a z/OS system

I've been learning about z/OS and MVS over the last couple of weeks using the Master the Mainframe course and also the highly affordable courses from Interskill. I wanted to build something proper so I built a thing that can backup a full z/OS system to CCKD files (same as what Hercules/Hyperion uses). With the fixes for 64-bit CCKD to Hyperion now merged, and the 64-bit cckddump tooling appears to be in progress, this might come in handy for some folks.

This is the CCKDALL JCL: