What are the different Linuxes:
You can run mainframe Linuxes without fear of the license policy. RHEL and SLES are battle-hardened supported commercial editions. Of course there are also free-of-cost mainframe Linuxes:
- Fedora s390x
- Debian s390
- Centos, using RHEL instructions
- Linux on System z has additional utilities and information.
The Hercules System/370, ESA/390, and z/Architecture Emulator site has a lot of great information, including installation and configuration. But check your favorite Linux distro first, because it may already include Hercules. Debian and its descendants include it, including the
herculesstudio graphical front-end. Fedora s390x is a nice bundle with a a good set of configuration files, such as an Ananconda installer configuration, a Hercules config, and boot files. I think openSUSE has the friendliest and best introduction to installing and running Hercules.
Remember your first experiences with Linux, the learning curve and how much time it took to become comfortable with it? It’s the same way with mainframes– they are significantly different from x86 servers, with a different vocabulary and different tools. But Linux on the mainframe is still Linux, so it’s not starting from scratch. Have fun, and everyone with any system Z or Hercules experience, please share some of your stories in the comments.
Related: Linux+Mainframe+Jobs Click here
What is Hercules Emulator(Wiki):
Hercules is a computer emulator allowing software written for IBM mainframe computers (System/370, System/390, and zSeries/System z) and for plug compatible mainframes (such as Amdahl machines) to run on other types of computer hardware, notably on low-cost personal computers.
Although there are other mainframe emulators performing a similar function, Hercules is significant in enabling private individuals to run mainframe computer software on their own personal computers.
Hercules runs under multiple parent operating systems including GNU/Linux, MS Windows, FreeBSD, Oracle Solaris, and Apple Mac OS X and is released under the open source software license QPL. It is analogous to Bochs and QEMU in that it emulates CPU instructions and select peripheral devices only. A vendor (or distributor) must still provide an operating system, and the user must install it. Hercules was notably the first mainframe emulator to incorporate 64-bit z/Architecture support, beating out commercial offerings.
Uses of Hercules Emulator
Many enterprises still rely heavily on mainframes, which makes it all the more difficult to get your hands on one and install Linux on it. The Hercules emulator gives you a full-fledged alternative.
Mainframes commonly are regarded as being reliable, but also big, complicated, pricey, and outmoded in today’s IT landscapes. Here, the Hercules mainframe editor, which emulates the CPU architecture, can help. Even if Linux is running in a production environment on a mainframe, Hercules still can provide a useful service for testing and development.
Download and Installation (Hercules)
Hercules 3.04 does not support current zLinux variants, which is why you should download the current source code for version 3.05. The RPM, also available from the homepage, will install but does not support network connections, making it unsuitable for the purposes of this article.
In a directory of your choice (e.g., /usr/local/src), unpack the sources, change to the/usr/local/src/hercules-3.05 directory, and enter configure as shown in Listing 1. After doing so, don’t forget to check config.log, paying particular attention to whether Zlib support is available. If the zlib-devel package is not installed on SUSE, you will still be able to build and use Hercules, but you will not be able to use the typical Zlib compressed virtual hard disks. Read for more click here