Before You Begin

Prerequisites

NMIS hast to be installed on the same server that opConfig is being installed on (NMIS version >=8.5.10G).
The individual performing this installation has a small bit of Linux experience.
Root access is available.
Internet access is required for installing any missing but required software packages.
opConfig requires a working MongoDB installation (ideally but not necessarily on the same server).
You will need a license for opConfig (evaluation licenses are available here).
All licenses are added/updated at https://<hostname>/omk/opLicense .

Preparation

If you do not yet have a working installation of NMIS in your server, please follow the procedure in the NMIS 8 Installation Guide.
Download opConfig from the Opmantek website.
If you have opConfig 1.X installed please check the upgrade guide first.

Installation Steps

As of February 2016, opConfig is distributed in a self-extracting download format that simplifies the installation process quite a bit. More information on running the installer can be found HERE: The Opmantek Installer

Transfer the opConfig installer file onto the server in question, either by direct download from the Opmantek website, or from your desktop with scp or sftp or a similar file transfer tool.

Start the interactive installer and follow its instructions:

sudo sh ./opConfig-Linux-x86_64-3.0.7.run
...
++++++++++++++++++++++++++++++++++++++++++++++++++++++
opConfig (3.0.7) Installation script
++++++++++++++++++++++++++++++++++++++++++++++++++++++
...
This installer will install opConfig into /usr/local/omk.
To select a different installation location please rerun the
installer with the -t option.

The installer will interactively guide you through the steps of installing opConfig. Please make sure to read the on-screen prompts carefully.
When the installer finishes, opConfig is installed into /usr/local/omk, and the default configuration files are in /usr/local/omk/conf, ready for your initial config adjustments.
A detailed log of the installation process is saved as /usr/local/omk/install.log, and subsequent upgrades or installations of other Opmantek products will add to that logfile.
For detailed information about the interactive installer please check the Opmantek Installer page.

Database Setup

If necessary the installer will offer to install MongoDB locally for you; if that is undesirable, or if you have a remote MongoDB installation that you want to use you'll need to adjust the MongoDB-related settings:
open conf/opCommon.nmis in an editor, go to the database section and change the server, username and password to reflect your MongoDB installation.
The result should look similar to the following (but there might be extra settings related to other products):

'database' => {
  'db_server' => 'localhost',
  'db_port' => '27017',
  'db_name' => 'nmis',
  'db_username' => 'opUserRW',
  'db_password' => 'op42flow42',
},

License

Access the opConfig GUI and acquire, restore or enter your license.
The opConfig GUI is accessible at http://<yourservername or ip address>/omk/opConfig/, and until you have entered a valid license neither the opConfig GUI nor the CLI tools will operate.

Configuration and Use

At this point opConfig should be ready for operation, but won't have any knowledge of which nodes to manage.

Your next step should be to consult the opConfig User Manual, which will tell you how to tell opConfig what commands to perform with which nodes, how to customize opConfig's behaviour to suit your needs and so on.

Please feel free to leave comments and suggestions below!

opConfig 3 Installation Guide