CCNP 3 Defining VLANs

Implementing Best Practices for VLAN Topologies

Describing Issues in a Poorly Designed network

Poorly design

Grouping Business Functions into VLANs

Scalable Network Addressing

Interconnection Technologies

Interonnection Technologies

Oversubscription Access to distribution layer links: The oversubscription ratio should be no higher than 20:1. That is, the link can be 1/20 of the total bandwidth available cumulatively to all end devices using that link. Distribution to core links: The oversubscription ratio should be no higher than 4:1. Between core devices: There should be little to no oversubscription planning. That is, the links between core devices should be able to carry traffic at the speed represented by the aggregate number bandwidth of all the distribution uplinks into the core.

Network traffic Types

Traffic types

Describing End-to-End VLANs

End-to-End VLANs

Describing Local VLANs

Local VLANs a genneraly confined to a wiring closet

Local VLANs should be created with physical boundaries rather than the job functions of the users on the end devices. Traffic from a local VLAN is routed to reach destinations on other networks. A single VLAN does not extend beyond the Building Distribution submodule.

Mapping VLANs in a Hierarchical network

Mapping VLANs

When mapping VLANs onto the new hierarchical network design, keep these parameters in mind. Examine the subnetting scheme that has been applied to the network and associate a VLAN to each subnet. Configure routing between VLANs at the distribution layer using multilayer switches. Make end-user VLANs and subnets local to a specific switch block. Ideally, limit a VLAN to one access switch or switch stack. However, it may be necessary to extend a VLAN across multiple access switches within a switch block to support a capability such as wireless mobility.

Implementing VLANs

VLAN Configuration modes

Global VLAN configuration mode

VLan Database mode

Explaining VLAN access Ports

VLAN access ports

VMPS - VLAN Membership Policy Server

Vlan Implementation

Implement VLAN commands

Implementing Trunks

Explaining VLAN Trunks

VLAN Trunks

Dot1Q and ISL

Describing ISL Trunks

ISL Encapsulation

Describing 802.1Q Trunking

802.1Q Trunking

802.1Q Tag

Explaining 802.1Q Nativ VLANs

Nativ VLAN

DTP Switchport Interactions

DTP Interactions

DTP Modes

Configuring a Trunk

Trunk Configuration

Propagating VLAN Configurations with VLAN Trunking Protocol

Explaining VTP Domains

VTP Domains

Describing VTP

VTP propagation

VTP Modes

VTP Modes

Describing VTP Pruning

VTP Pruning

Describing VTP Operation

VTP Operation

VTP Advertisements:

VTP Summary

VTP Subset

VTP Request

VTP Configuration

VTP Confguration Steps

VTP Configuration

Step 1 Establish a design specifying which switches are server, client, or transparent, and what the boundaries are for the VTP domain. Step 2 Verify the current VLAN information on any switch that will be configured as server. Step 3 Specify the VTP password (optional). Step 4 Specify the version number, if other than the default. Step 5 Specify the VTP domain name (case-sensitive). Step 6 Configure the VTP mode. Step 7 Verify the configuration. Step 8 Verify that updates are being sent from or received by the switch as intended.

Correcting Common VLAN Configuration Errors

Describing Issues with 802.1Q Native VLAN

Nativ VLAN Mismatch

Adding New Switches to an Existing VTP Domain

Revision error

Describing Trunk Link Problems

Trunk Link

Common Problems with VTP Configuration

Common VTP Problems