Tech blog

This blog is intended as a tech blog targetting other network admins as well as some home automation projects. All information and tutorials are provided as-is and there is no guarantee this will work exactly the same in your environment. All posts are my own and do solely reflect my own opinion and not that of my employer.

Nexus 9k VPC (back to back) and FHRP setup in 2 data centers

This post describes the setup of VPCs on a data center interconnect and HSRP as the first hop redundancy protocol for the VLAN interfaces (SVIs). This configuration has been performed on a Nexus 93180YC-EX with software version 7.0(3)I7(8). The switches have the system default switchport command set, so all ports are switchports by default, but this does not matter for the setup. Background This configuration is for a setup where the current network “core” is a Catalyst 6500 in VSS mode with a chassis in each data center. [Read More]
Cisco  Nexus  VPC  FHRP  HSRP 

Cisco vEdge Cloud Certificate Installation

Like some of the other articles I’ve written, this serves mostly as a documentation page to myself. The last time I had to manually install a certificate on a vEdge cloud router was six months ago, so it’s something you easily forget. This guide was written for vEdge Cloud 18.3.3. Installing a vEdge Cloud router It’s fairly easy to install the vEdge Cloud router. There are images available for VMs in all the major clouds. [Read More]

Network Automation Tools

Network automation was THE network topic of 2019, and perhaps for 2020 as well, although COVID-19 is a strong candidate as well. However, network automation not a new idea or technology. It’s becoming more prevalent in our networks through vendors (finally) adding more API support, but also products such as Cisco DNA Center, various SD-WAN products and so on; Networks with controllers that provide a programmatic interface. In the age of DevOps, everything needs an API and networking vendors are finally coming around to supporting it. [Read More]

VSCode for network engineers

I would like to share with you my favorite tool for my work available on Windows. Why favorite? Well, Linux and MacOS have all the other tools (iterm2 anyone?) that are not available on Windows so the competition is not that amazing. Apart from that, it must be said that VS Code is an absolute killer-app. A swiss army knife if you will of text editing, coding and syntax highlighting. I use this tool for almost anything except e-mail. [Read More]
Code  Tools 

Solarwinds queries repo

Today I would like to quickly point out that I’ve started to ‘open source’ some of my Solarwinds queries. I’ve noticed a lot of people on the web struggling with getting more out of this product. I’ve added a new (public) repo under my github profile that might help fellow network admins get a bit more useful info out of their Solarwinds instances. Solarwinds is a nice tool, but it’s definitely missing some very basic info regarding network devices. [Read More]

Solarwinds - Monitoring DMVPN

Again, this week a request for Solarwinds reporting utilizing some SQL knowledge on my part. The idea was to create a report on DMVPN connections. The build-in web reporter does a fairly decent job creating this report already. However, the IP addresses in this report do not reflect the actual interface addresses (or perhaps it’s an user issue ;) ). Query Solarwinds Start by opening and connecting to the Solarwinds database in SWQL Studio. [Read More]

Solarwinds - Duplicate switch stackmembers

This is a follow up post to the switchstack sql code from last week. Recently, I noticed issues with my CPU stack member reporting, which showed duplicates. It turns out that there were duplicate entries in the SwitchStackMember table through some problems with Orion recently (don’t ask me the details, I’m not the admin). The problem resulted in the same node and stackswitches having several unique stack id’s in this table, thus being reported several times. [Read More]

Solarwinds - Monitoring switch stacks

Today’s post is on using SQL queries in Solarwinds to get more detailed information on the frontpage on stackswitches. Solarwinds tends to average the memory and cpu utilization among all switches in a stack, but this does not always reflect the true statistics on the switches. Sustained CPU above 80% can lead to data packets being dropped. The queries are all build in SWQL studio on a Solarwinds server to verify the information that is returned. [Read More]

Installing HomeAssistant ( on CentOS

In this piece we’ll be installing Home Assistant in Docker on CentOS. The reasons why I chose CentOS and how to set it up are described in the following posts: Set up a secure home server with CentOS - Part 1 Set up a secure home server with CentOS - Part 2: Samba Because of scalability and administratability, I’ve decided go to with Docker containers this time. My Pi already runs Hass. [Read More]

Set up a secure homeserver with CentOS - Part 2: Samba

Hey all, this is part 2 of setting up an CentOS server. For backup and accessibility, I always set up a Samba share. Samba is a filesharing protocol supported by Microsoft Windows, Linux and MacOS and I therefor prefer this type of fileshare over others in terms of compatibility. If you want to see other parts of this series: Set up a secure home server with CentOS - Part 1 Samba can be challenging to set up because of the complexity and the amount of configuration options, however, for the purpose of a homeserver, we’ll keep it simple. [Read More]