IS-IS Overview Intermediate system to intermediate system (Short for IS-IS) is an IGP link-state protocol which builds a link-state database. Like OSPF, It will the run the Dijkstra SPF algorithm to find the best path to the destination. IS-IS has an AD of 115 with Cisco NX-OS. Unlike OSPF, IS-IS does not run over network […]
BGP Overview Border-Gateway Protocol (BGP) is an extremely scalable routing protocol which gives you a lot of control to choose the best route. It is a path-vector, which unlike OSPF where routers individually run SPF algorithm on their Link-State Database, it advertises the routes to the network. BGP connects two autonomous systems (AS) to teach […]
OSPFv2 Overview With Open-Shortest Path First (OSPF) as a Link-State routing protocol, routers build some information about the network. Those information include: Router ID Number of Links Links Descriptions Attached Router Subnet Mask Metric The routers multicast these information (Link State Advertisement or LSA) to the segment. As a result, all routers in the same […]
STP Features In this section we will discuss on different improvement which added to the Rapid spanning-tree. In particular we talk about: Convergence Optimization Edge Port STP Filters BPDU Filter BPDU Guard Root Guard Unidirectional Link Detection Loop Guard Bridge Assurance Convergence Optimization Spanning-Tree Edge Port This is equivalent of PortFast feature with Common Spanning-Tree. […]
Audiences: Candidates who want to prepare for CCIE Data Center (v3.0) Introduction to NX-OS Command Line In this section, we assume that you know how to connect to a NX-OS CLI via a terminal emulator program. Here is how we bootstrap our Nexus switch for the first time. If you skip Power On Auto Provisioning, […]
A Brief Introduction to MST IEEE 802.1s originally started as Cisco’s Multiple Instances Spanning Tree Protocol (MISTP). Remember that RapidPVST+ each VLAN is mapped to a single spanning tree instance. When you have 200 VLANs, it means there are 200 instances of spanning tree. This requires a lot of CPU power and memory. You can […]
A Brief Evolution of Spanning-Tree Protocols on NX-OS Before discussing on IEEE 802.1w, I would want to present a brief history of Spanning-tree evolution, the we continue with our main subject of this post. Spanning-tree is the loop prevention mechanism in Layer-2. According to graph theory: Spanning: A spanning graph is a subgraph obtained by […]
Audiences: Candidates who want to prepare for CCIE Data Center (v3.0) Scope: 1.1.b Tagging/Trunking from CCIE Data Center (v3.0) Exam Topics – Practical Exam Inter-VLAN Routing Although we can route between two VLANs with a router 802.1Q trunk (Router-On-A-Stick AKA ROAS), but that is not in the scope of our CCIE Data Center curriculum; instead, […]
Audiences: Candidates who want to prepare for CCIE Data Center (v3.0) Scope: 1.1.b Tagging/Trunking from CCIE Data Center (v3.0) Exam Topics – Practical Exam Virtual Local-Area Network (VLAN) You can take a physical LAN switch which does not break the broadcast domain and logically break it into multiple broadcast domains. You are doing this by […]
In this article we are going to talk about the differences between Distance Vector and Link State dynamic routing protocols. Link State Routing Protocols In order to understand the major difference of Link-State Routing Protocols compared to Distance Vectors, we want to implement a simple network with four routers. we will run one of the […]
Elissa Garlin
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