Config Router

  • Google Sheets
  • CCNA Online training
    • CCNA
  • CISCO Lab Guides
    • CCNA Security Lab Manual With Solutions
    • CCNP Route Lab Manual with Solutions
    • CCNP Switch Lab Manual with Solutions
  • Juniper
  • Linux
  • DevOps Tutorials
  • Python Array

Understanding Enhanced Interior Gateway Routing Protocol (EIGRP)

March 29, 2020 by Marques Brownlee

Understanding Enhanced Interior Gateway Routing Protocol (EIGRP) Metrics EIGRP and IGRP use the same equation to calculate their metrics; however, the EIGRP metric is obtained by multiplying the IGRP metric by 256. In other words: where the IGRP metric is shown in Equation 6-1. By default, the K values of K1 and K3 are 0; therefore, the EIGRP metric simplifies to … [Read more...]

Filed Under: CCIE, Cisco Tagged With: DUAL Finite-State Machine, EIGRP Behavior, EIGRP Neighbor Relationships, EIGRP Packet Format, EIGRP Reliable Transport Protocol, EIGRP Summarization, Metrics

Troubleshooting EIGRP

March 29, 2020 by Marques Brownlee

Troubleshooting EIGRP Troubleshooting EIGRP Neighbor Relationships This section discusses methods of troubleshooting issues regarding EIGRP neighbor relationships. The following are the most common causes of problems with EIGRP neighbor relationships: Unidirectional link Uncommon subnet, primary, and secondary address mismatch Mismatched masks K value … [Read more...]

Filed Under: CCIE, Cisco Tagged With: EIGRP Error Messages, Troubleshooting EIGRP, Troubleshooting EIGRP Dial Backup Problem, Troubleshooting EIGRP Neighbor Relationships, Troubleshooting EIGRP Redistribution Problems, Troubleshooting EIGRP Route Advertisement, Troubleshooting EIGRP Route Flapping, Troubleshooting EIGRP Route Installation, Troubleshooting EIGRP Route Summarization

Understanding Open Shortest Path First (OSPF)

March 29, 2020 by Marques Brownlee

Understanding Open Shortest Path First (OSPF) OSPF Packet Details OSPF has five types of packets used for various reasons. Table 8-1 documents the different OSPF packet types and describes their functionality. All the OSPF packet types share a common 20-byte OSPF protocol header. Figure 8-1 shows the common OSPF protocol header format. The list that follows … [Read more...]

Filed Under: CCIE, Cisco Tagged With: OSPF Adjacencies, OSPF Areas, OSPF LSA Details, OSPF Media Types, OSPF Packet Details, Understanding Open Shortest Path First (OSPF)

Troubleshooting BGP Filtering

March 6, 2020 by Marques Brownlee

Troubleshooting BGP Filtering BGP offers a powerful filtering mechanism when advertising or receiving BGP routes. Filtering rules are defined based on the BGP peering relationship. An ISP might want to exchange full BGP routes to another ISP but might want to give only partial routes to its enterprise customer. On the other hand, an enterprise customer might want to advertise … [Read more...]

Filed Under: CCIE, Cisco Tagged With: AS_PATH Filtering Using Regular Expressions, Extended Access Lists Fails to Capture the Correct Masked Route, Standard Access List Fails to Capture Subnets, Troubleshooting BGP Filtering

Troubleshooting BGP Best-Path Calculation Issues

March 6, 2020 by Marques Brownlee

Troubleshooting BGP Best-Path Calculation Issues Chapter 14 discusses in detail how the BGP best-path algorithm works to select a single best route out of many to install in the IP routing table and to advertise to other BGP neighbors. This section discusses a few cases that deal with scenarios in which best-path selection does not work as intended. The following are the … [Read more...]

Filed Under: CCIE, Cisco Tagged With: Lowest MED Not Selected as Best Path, Path with Lowest RID Is Not Chosen as Best, Troubleshooting BGP Best-Path Calculation Issues

Troubleshooting Load-Balancing Scenarios in Small BGP Networks

March 6, 2020 by Marques Brownlee

Troubleshooting Load-Balancing Scenarios in Small BGP Networks Problem: Load Balancing and Managing Outbound Traffic from a Single Router When Dual Homed to Same ISP—Cause: BGP Installs Only One Best Path in the Routing Table In multihomed scenarios, a common concern that enterprise network operators face is improperly utilizing the external links going to the ISP. Typically, … [Read more...]

Filed Under: CCIE, Cisco Tagged With: Problem: Load Balancing and Managing Outbound Traffic from a Single Router When Dual Homed to Same ISP—Cause: BGP Installs Only One Best Path in the Routing Table, Troubleshooting Inbound IP Traffic Flow Issues Because of BGP Policies

Troubleshooting Outbound IP Traffic Flow Issues Because of BGP Policies

March 6, 2020 by Marques Brownlee

Troubleshooting Outbound IP Traffic Flow Issues Because of BGP Policies BGP's real power is in managing IP traffic flows coming in and going out of the AS. BGP in general and Cisco IOS Software in particular offer a great deal of flexibility in manipulating BGP attributes LOCAL_PREFERENCE, MED, and so forth to control BGP best-path calculation. This best-path decision … [Read more...]

Filed Under: CCIE, Cisco Tagged With: Asymmetrical Routing Occurs and Causes a Problem Especially When NAT and Time-Sensitive Applications Are Used—Cause: Outbound and Inbound Advertisement, Troubleshooting Outbound IP Traffic Flow Issues Because of BGP Policies

Troubleshooting BGP Route-Reflection Issues

March 6, 2020 by Marques Brownlee

Troubleshooting BGP Route-Reflection Issues Route reflectors (RR), discussed in RFCs 1966 and 2796, are used to avoid IBGP full mesh in an AS, as required by RFC 1771. Route reflection ensures that all IBGP speakers in an AS receive BGP updates from all parts of the network without having to run IBGP between all the routers in the network. Route reflection reduces the number … [Read more...]

Filed Under: CCIE, Cisco Tagged With: Loss of Redundancy Between Route Reflectors and Route-Reflector Client—Cause: Cluster List Check in RR Drops Redundant Route from Other RR, Route-Reflector Client Stores an Extra BGP Update—Cause: Client-to-Client Reflection, Troubleshooting BGP Route-Reflection Issues

Troubleshooting BGP Route Not Installing in Routing Table

March 6, 2020 by Marques Brownlee

Troubleshooting BGP Route Not Installing in Routing Table This section discusses issues related to BGP routes not getting installed in the IP routing table. If a router must forward an IP packet by looking at the IP destination address in IP packet, the router must have an IP routing table entry for the subnet of the IP destination address. If the BGP process fails to … [Read more...]

Filed Under: CCIE, Cisco Tagged With: EBGP-Learned Route Not Getting Installed in IP Routing Table, IBGP-Learned Route Not Getting Installed in IP Routing Table—Cause: IBGP Next Hop Not Reachable, Problem: EBGP-Learned Route Not Getting Installed in IP Routing Table, Troubleshooting BGP Route Not Installing in Routing Table

Troubleshooting BGP Route Advertisement /Origination and Receiving

March 6, 2020 by Marques Brownlee

Troubleshooting BGP Route Advertisement /Origination and Receiving Another common problem after neighbor relationship issues that BGP operators face occurs in BGP route advertisement/origination and receiving. BGP originates routes only by configuration. However, it needs no configuration in receiving routes. Larger ISPs originate new BGP routes for their customers on a … [Read more...]

Filed Under: CCIE, Cisco Tagged With: BGP Route Not Getting Originated—Cause: BGP Is Autosummarizing to Classful/Network Boundary, Problem in Propagating BGP Route to IBGP Neighbor but Not to EBGP Neighbor—Cause: BGP Route Was from Another IBGP Speaker, Problem in Propagating IBGP Route to IBGP/EBGP Neighbor—Cause: IBGP Route Was Not Synchronized, Problem in Propagating/Originating BGP Route to IBGP/EBGP Neighbors—Cause: Misconfigured Filters, Troubleshooting BGP Route Advertisement /Origination and Receiving

Next Page »

Recent Posts

  • How do I give user access to Jenkins?
  • What is docker volume command?
  • What is the date format in Unix?
  • What is the difference between ARG and ENV Docker?
  • What is rsync command Linux?
  • How to Add Music to Snapchat 2021 Android? | How to Search, Add, Share Songs on Snapchat Story?
  • How to Enable Snapchat Notifications for Android & iPhone? | Steps to Turn on Snapchat Bitmoji Notification
  • Easy Methods to Fix Snapchat Camera Not Working Black Screen Issue | Reasons & Troubleshooting Tips to Solve Snapchat Camera Problems
  • Detailed Procedure for How to Update Snapchat on iOS 14 for Free
  • What is Snapchat Spotlight Feature? How to Make a Spotlight on Snapchat?
  • Snapchat Hack Tutorial 2021: Can I hack a Snapchat Account without them knowing?

Copyright © 2025 · News Pro Theme on Genesis Framework · WordPress · Log in