Tag Archives: design

How to safely transform a routing domain

As part of my job as a Senior Network Engineer, I develop procedures for undertakings of varying complexity. In this post I’m describing a technique that greatly simplifies any project where a routing domain is expected to churn (i.e. neighborships going up and down, routes flapping), when such event is undesirable. Motivation I developed this technique for a… Read More »

Dual-homing with Policy-Based Routing – a case study

Policy-based routing allows network administrator to stir traffic in directions different from the one chosen by destination-based routing and its routing protocols. This can be useful in several scenarios, namely in dual-homing to different ISPs, as well as other special cases. Using policy-based routing for dual-homing General notes on dual-homing The term Dual-homing in its most general meaning… Read More »

VLAN allocation

Speaking of L2 design, there are several aspects to the VLAN allocation on the switches: standard and extended VLAN ID ranges, reserved IDs, internal usage, protocol limitations and design best practices.