Design Guide
© 2008 Cisco Systems, Inc. All rights reserved. This document is Cisco Public Information.
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VLAN Configuration
To configure the VLANs on the switches, complete the following tasks:
Set the VTP administrative domain name and mode and create the server-farm VLANs as follows:
(config)# vtp domain <domain name>
(config)# vtp mode transparent
(config)# vlan 60
(config-vlan)# name bladeservers
(config-vlan)# state active
RPVST+ Configuration
Configure Spanning Tree Protocol to manage the physical loops in the topology. Cisco
recommended using RPVST+ for its fast-convergence characteristics. Set the Spanning Tree
Protocol mode on each aggregation switch as follows:
(config)# spanning-tree mode rapid-pvst
Configure the path cost to use 32 bits in the Spanning Tree Protocol calculations:
(config)# spanning-tree pathcost method long
Configure the primary and secondary root switches as follows:
(config)# spanning-tree vlan <vlan range> root primary | secondary
Inter-Switch Link Configuration
The topologies discussed in this guide require connectivity between the switches. The following
three types of interswitch connections exist:
●
Aggregate 1 to aggregate 2
●
Aggregate 1 or aggregate 2 to HP c-Class BladeSystem switch A or switch B
●
HP BladeSystem switch A to switch B
Each of these connections is a Layer 2 Cisco EtherChannel connection consisting of multiple
physical interfaces bound together as a channel group or port channel. These point-to-point links
between the switches should carry more than one VLAN; therefore, each is a trunk.
Port-Channel Configuration
Link Aggregate Control Protocol (LACP) is the IEEE standard for creating and managing Cisco
EtherChannel connections between switches. Each aggregate switch uses this feature to create a
port channel across the line cards. The use of multiple line cards within a single switch reduces the
possibility of the point-to-point port channel becoming a single point of failure in the network.
Configure the active LACP members on aggregate 1 to Cisco Catalyst Blade Switch 3020 switch A
as follows:
(config)# interface GigabitEthernet12/1
(config-if)# description <<** Connected to Switch-A **>>
(config-if)# channel-protocol lacp
(config-if)# channel-group 1 mode active
(config)# interface GigabitEthernet11/1
(config-if)# description <<** Connected to Switch-A **>>
(config-if)# channel-protocol lacp
