Contest Systems Overview
Connectivity Guide

Operating System Services

z/OS has various services that you will be connecting to during the course of the contest. These services are listed below along with corresponding port numbers for client connectivity. You may need to communicate the following information to your network administrator to ensure the following ports and services are available:

z/OS IP Address :
Service Port
3270 23
SSH 22
FTP 21
RDz (Optional) 4035

Please take the time to validate communication path
From workstation command prompt:

If ping is unsuccessful, then contact local network administrator.
When contacting network administrator, pass along IP address and above Port numbers.
Workstation or network firewall software can block IP addresses and Port numbers needed to participate in this contest.

Contest Environment

In recent years, the contest environment had multiple operating systems for you to connect to. This year, we are only using z/OS. However, you will be using two different clients to communicate with different operating environments inside z/OS. The different environments are:

  • z/OS Multiple Virtual Storage (MVS)
  • z/OS Unix System Services (USS)

z/OS is running as a virtual machine on a single physical IBM Z mainframe in a development lab subject to planned and scheduled unavailability from the public internet.

Note: During a regularly scheduled interval, the IBM Z development lab that hosts the Master the Mainframe contest is unavailable from approximately 9:30am to 3:30pm every other Sunday in central USA time zone.

Click here to view the outage schedule.

Next: Required Workstation Software