In my previous 2 posts I played around Linux Networking with the module iproute2. How to configure 1 Linux host with 2 NICs and 2 default gateways How to setup 2 network isolated Docker containers (front-end and back-end) Now that pure routing is done, the next step is iptables, as a Firewall module. I’ve to admit …
Making this work might sound crazy, but if Docker has to be comparable in functionalities already provided by other types of virtualization, then this has to work right? Ok, this is the scenario, is a classic one: I need to deploy in one Docker host, 2 isolated containers, let’s say front-end and back-end. The Linux …
Historically, it was not possible to have 2 default gateways in a Linux host. You can SEND traffic to both NICs, but the reply will always come from the NIC which has the default gateway. This will generate asymmetric traffic and it will be denied in the network or by the originating host. Asymmetric traffic …
Some time ago I was asked for help to develop a “simple and quick” Python script to monitor the status of a Linux service. They were in the middle of a deployment and they needed something fast. They added, keep the result in a JSON file with the date, serve the directory with HTTP for …
In the previous post, we tried Netmiko from: the most basic command to one device, to the whole inventory, and as a bonus filtering devices to stay in a loop to keep throwing command, very useful for troubleshooting scenarios. The timing was already good in comparison to doing it completely manually. Between 6 and 10 …
Start using Netmiko is easier than you might think. Going from being a pure network guy to network automation with software development skills is NOT easy, and it is a long shot. Usually, people (like me) start with Ansible just because it is easier when you don’t know much about Python. Plus you can get …