Arista configure session

To configure an Arista, you can jump in configuration mode and start firing off your configuration commands one after the other and have the changes take effect immediately. Quite a few people that I have spoken with, people that have been working with Arista‚Äôs for several years, took this approach... [Read More]


Up until this point in my career, most of my scripting efforts involved PyEZ, Paramiko and Netmiko. But after having to work with multiple vendors inside SaltStack, I started looking into NAPALM. This post is a short summary of what I have learned so far about NAPALM in general. [Read More]

6VPE between Juniper MX and Cisco IOS XR

In this post, we will enable an existing MPLS L3VPN for IPv6 using 6VPE. We will extend the cust-1 VPN in the topology we used during my last post, MPLS L3VPN between Juniper MX and Cisco IOS XR, and enable 6VPE across Cisco IOS XR and MX routers to connect... [Read More]

Exploring the Arista eAPI using pyeapi.

The Arista EOS command API, or eAPI, has been maturing ever since EOS 4.12. Recently, I started to look into ways to use this API for information retrieval. In this article, I am sharing what I learned exploring the eAPI using a library called pyeapi. [Read More]

Templating for network engineers in SaltStack.

Templating in SaltStack is an absolute joy. It makes the generation of text-based configurations for networking devices very easy. This write up is to give you some tips and insights that I could have used when I started templating myself. After walking you through an easy way to render templates... [Read More]

Getting your facts straight.

The Salt grains interface is a very powerful tool. The interface presents Salt with grains of information about the system that is being managed. One of the things you can use grains for is to make your templating more effective. As a network engineer, I mostly work with proxy-minions. And... [Read More]

Troubleshooting packet loss with firewall filters

Packet loss can be caused by all sorts of reasons. Could be faulty hardware, a software issue on a device, a congested link or some policers and shapers that are working against you. In order to fix packet loss in a network, you first have pinpoint where the packets are... [Read More]
Tags: juniper

Introducing packet loss with RED

Recently, a customer had several issues going on at the same time. The customer had an MPLS L3VPN with a default route towards a central firewall in the datacenter. Behind this firewall, there was some rackspace and a cloud environment. A lot of components were involved and after solving the... [Read More]
Tags: juniper