CCDP Study Guide - High Availability Design - Part 2

    High Availability Design - Part 2


    Access Layer High Availability


    Within hardware

    redundant power supplies

    redundant supervisor engines


    Between hardware

    default gateway redundancy between multiple distribution layer

    first hop redundancy protocols


    Stackwise Technology




    3750 Workgroup switch

    etherswitch services module


    connect switches using special cables to form a single logical unit


    single management interface


    the special cable used create a bidirectional path that act as a the fabric switch



    IOS 12.2(18) SXD for 6500/7600 Switches


    Control Plane Policing (CoPP)


    Nonstop Forwarding (NSF)


    Stateful Switchover (SSO)


    Gateway Load Balancing Protocol (GLBP)



    GLBP vs HSRP


    it is very easy to have load balancing using GLBP


    load balancing using HSRP is not so easy and it can lead to errors and problems


    Core and Distribution Layer Design


    redundancy within and between layers


    it is necessary to have network bandwidth and port density capacity planning



    Optimal Redundancy


    OSPF and EIGRP timer manipulation after carefully evaluation


    redundant supervisor engines with NSF and SSO may conflict with modified IGP timers


    NSF and SSO most commonly deployed at the network edge for use with peer-to-peer links to providers


    NSF with SSO


    fast supervisor switchover


    new route processor takes over when there is a failure


    synchronizes: arp, QoS, ACLs, FIB, startup config, running config



    NSF - Non Stop Forwarding


    continue packet forwarding (EIGRP, OSPF, IS-IS, BGP)



    Nexus Line - Cisco Equipment


    extremely modular


    processes are also modular



    6500 Series Multilayer Switch with IOS Software Modularity


    resilent control plane


    fault containment and stateful process




    cisco IOS-XR (high availability IOS) is based on UNIX QNX


    uses EEM - Embedded event manager



    Spanning Tree Protocol


    STP is needed because there are some designs that look for it:


    VLAN spans access layer switches for business applications support


    protect against user-side loops


    datacenter applications on a server farm




    This Study Guide is based on the book "Designing Cisco Network Service Architectures" written by John Tiso and published by Cisco Press.

    It is a personal group of notes and topics created with the intention of helping my studies for the Cisco CCDP Certification.