Vendor Quirks & Common Pitfalls in BGP Configuration
In this post, I walk through some key quirks and common pitfalls you might encounter when configuring BGP on MikroTik RouterOS (v6 & v7), Cisco IOS, Juniper Junos, and Arista EOS.
Internet Architecture
Interconnection, peering, Data centers. How the Internet works. IXPs, transit, and other topics. Routing and Control Planes such as BGP and OSPF protocols. RPKI and IP resources are also covered.
Juniper BGP Configuration .set and templates for my Patreon Subscribers. Free Info Post
I have created a series of example configurations, a commented PDF, and a Juniper .set for configuring BGP on Juniper routers. This post is available for my Patreon folks here.
Juniper BGP Configuration .set and templates for my Patreon Subscribers. $15
This content is for Patreon subscribers of the j2 blog. Please consider becoming a Patreon subscriber for as little as $1 a month. This helps to provide higher quality content, more podcasts, and other goodies on this blog.To view this content, you must be a member of Justin’s Patreon at $15 or more Unlock with … Read more
BGP Filtering Best practices for fun and security
Border Gateway Protocol (BGP) filtering is critical for securing and optimizing internet routing. Improper BGP configuration can lead to serious issues like route leaks, hijacks, or suboptimal routing. Here are the most effective best practices for BGP filtering: 1. Prefix Filtering Objective: Ensure only authorized prefixes are advertised or accepted. 2. AS-PATH Filtering Objective: Prevent … Read more
Enterprise Guide to Selecting a Colocation Data Center
This guide outlines the critical factors enterprises should consider when selecting a colocation partner.
Cisco BGP Troubleshooting: Essential Commands Every Network Engineer Should Know
When BGP (Border Gateway Protocol) misbehaves, the ripple effect can be massive—routes disappear, prefixes flap, and connectivity grinds to a halt. Whether you’re managing a large enterprise edge or an ISP core, knowing how to quickly diagnose BGP issues on Cisco routers is critical. Here’s a hands-on guide to the most useful Cisco IOS BGP … Read more
Border Gateway Protocol (BGP): How the Internet’s Routing Protocol Works
Border Gateway Protocol (BGP) is a protocol that makes the Capital I Internet run. It is the fundamental system that Internet Service Providers (ISPs) and large networks use to exchange reachability information and ensure data finds its way across the complex web of networks making up the global Internet. This post will demystify how BGP … Read more
Private vs. Public Autonomous System Numbers (ASN): What’s the Difference?
In the world of internet networking, Autonomous System Numbers (ASNs) play a crucial role in routing data efficiently between different networks. ASNs are unique identifiers assigned to Autonomous Systems (AS)—large networks or groups of IP addresses that operate under a single organization, such as ISPs, cloud providers, or large enterprises. However, not all ASNs are … Read more
Power Cabling Do’s and Don’ts in a data center
This content is for Patreon subscribers of the j2 blog. Please consider becoming a Patreon subscriber for as little as $1 a month. This helps to provide higher quality content, more podcasts, and other goodies on this blog.To view this content, you must be a member of Justin’s Patreon Unlock with PatreonAlready a qualifying Patreon … Read more
Patreon Post: Mikrotik tagging incoming routes with a community
This content is for Patreon subscribers of the j2 blog. Please consider becoming a Patreon subscriber for as little as $1 a month. This helps to provide higher quality content, more podcasts, and other goodies on this blog.To view this content, you must be a member of Justin’s Patreon Unlock with PatreonAlready a qualifying Patreon … Read more
IPv4 Subnet Mask Cheat Sheet: A Handy Guide
IPv4 Subnet Mask Cheat Sheet CIDR Notation Subnet Mask Total Subnets Hosts per Subnet (usable) /8 255.0.0.0 1 16,777,214 /9 255.128.0.0 2 8,388,606 /10 255.192.0.0 4 4,194,302 /11 255.224.0.0 8 2,097,150 /12 255.240.0.0 16 1,048,574 /13 255.248.0.0 32 524,286 /14 255.252.0.0 64 262,142 /15 255.254.0.0 128 131,070 /16 255.255.0.0 256 65,534 /17 255.255.128.0 512 32,766 … Read more
Understanding the Types of Power in a Data Center
A data center is the beating heart of modern businesses, housing critical IT infrastructure that powers applications, processes, and data. Behind this infrastructure lies a robust power system designed to ensure uninterrupted operation. Power systems in a data center are complex and include various types of power sources and components, each serving a unique purpose. … Read more