Quick manual Kafka OpenNMS stack

2021-08-05 2 min read OpenNMS Tutorial Just-the-Fun-Parts Ronny Trommer

We have gathered a few ready-to-run Docker stacks in our public stack-play GitHub repository. But sometimes you need Kafka, Zookeeper and OpenNMS quickly on a baremetal deployment without Docker. Here a few quick notes how to get the bare minimum up and running.

Zookeeper

Install OpenJDK 11 JRE

sudo apt install -y openjdk-11-jre

Create a user for zookeeper

sudo adduser --system --home /opt/zookeeper --disabled-login zookeeper

Create a logs directory

sudo mkdir /var/log/zookeeper
sudo chown zookeeper:nogroup /var/log/zookeeper -R

Install zookeeper

SSL and Java

2018-11-26 3 min read Tutorial Technology Ronny Trommer

Running applications with a current Java is not a big deal thanks Let’s Encrypt. This article describes what happens if you want to authenticate your OpenNMS against LDAP using SSL with a self-certified certificate.

First of all I assume you have confiured verything so you can authenticate against LDAP in plaintext and you got a role mapping as you wanted it. If not you can have a look here.

So the naive approach would be, just changing the line in your activeDirectory.xml from

Send notifications with Signal

2018-11-01 3 min read OpenNMS Tutorial Ronny Trommer

In some cases it is nice to have notifications from OpenNMS in a separate channel on a smartphone and you don’t want to pay for SMS. Here is a tutorial where I use Signal using the signal-cli.

This Howto will describe how to download the latest signal-cli tool, link it to your existing Signal account and how to configure OpenNMS to use it as a notification target. You should have already an OpenNMS Horizon or Meridian running and you need a Signal account with the Signal app installed and configured on your smartphone.

Monitoring Websites with OpenNMS

2018-07-27 4 min read Tutorial OpenNMS Ronny Trommer

Monitoring websites is a common requirement. Using OpenNMS to monitor websites can be done by using the built in HTTP/HTTPS based monitors.

While a “Node” can be pretty much everything in a network, the internal model to monitor something is pretty old-fashioned and static. Monitoring a service requires to assign a service to an IP address.

This article describes a pattern how you can monitor web sites with low maintenance and without the need to maintain for each website a monitor which is cumbersome in maintenance.

Authenticate OpenNMS Horizon with FreeRADIUS

2018-07-22 2 min read Tutorial OpenNMS Ronny Trommer

Centralized authentication is a core service as soon you have a network with more than 3 computers. This article is about how to authenticate a OpenNMS Horizon 22.0.2 using RADIUS provided by a FreeRADIUS service.

In this example the FreeRADIUS server is configured to provide 3 users. A dictionary is configured which returns 2 roles, ROLE_USER and ROLE_ADMIN which can be used to decide which security role is assigned in the OpenNMS Horizon Web UI.

Authenticate OpenNMS Horizon with Active Directory on Windows Server 2016

2018-07-16 3 min read Tutorial OpenNMS Ronny Trommer

Centralized authentication is a core service as soon you have a network with more than 3 computers. This article is about how to authenticate a OpenNMS Horizon 22.0.1 against an Active Directory provided on a Microsoft Windows Server 2016. I’ll focus here on the Active Directory and Spring configuration parts, securing the connection with LDAPS and using self-signed certificates in Java is another topic and not covered here.

In this example the domain is called labmonkeys.local and the Microsoft Windows Server has the IP address 192.168.178.220. The user name for the bind user is OpenNMS Bind User with the password MyPass123!.

Build OpenNMS with Docker

2018-07-14 4 min read Tutorial OpenNMS Ronny Trommer

Being able to compiling an open-source project is important. You can change the code, so you should also able to build it.

Why is there a dedicated Docker image for the build environment? The dependencies running a pre-build OpenNMS Horizon distribution and compiling from source are different. To build OpenNMS Horizon you need Apache Maven and to compile JICMP, JRRD you need a C compiler environment. This is nothing you want to carry when you just want to run OpenNMS Horizon.

Zyxel vs. Vodafone Easybox with VDSL 50

2016-07-14 1 min read Tutorial Technology Ronny Trommer

I ran in some trouble with my Vodafone Easybox 904 xDSL. Even with 2Ghz and 5Ghz WLAN I had regularly drops. Had to turn on / off the WLAN on the device or had to reboot it to reconnect. Otherwise the VDSL line reguarly got disconnected, also replacing the Easybox from Vodafone didn’t helped, so I bought a Zyxel VMG1312-B30A.