Configuring PowerConnect and Cisco Switches for iSCSI SANs

The below are extracts taken from the pdf “Dell EqualLogic Configuration Guide – A guide to building an iSCSI based SAN solution with Dell EqualLogic PS Series Arrays.” This is nice information to have to hand when in the field. The document is for EqualLogic but is applicable to most iSCSI SAN solutions.

General Requirements for Switches When Used with EqualLogic PS Series Arrays

> Non-Blocking backplane design

> Support for Inter-Switch Linking (ISL) or Dedicated Stacking Architecture

> Support for creating Link Aggregation Groups (LAG)

> Support for active or passive Flow Control (802.3x) on ALL ports

> Support for Rapid Spanning Tree Protocol (R-STP)

> Support for Jumbo Frames

> Ability to disable Unicast Storm Control

> Adequate Buffer Space per switch port

PowerConnect 54xx Switch Configuration – CLI Commands

To enter privileged mode:

switch> enable

To enter configuration mode:

switch# configure

To exit configuration mode (and any level), save running-config to startup-config (IMPORTANT), then exit priviledged mode:

switch(config)# exit

switch# copy running-config startup-config

switch# exit

To configure Port 10:

switch(config)# interface ethernet g10

To configure all ports g1 to g15:

switch(config)# interface range ethernet g(1-15)

To disable iSCSI optimization setting (QoS for iSCSI frames to have priority – designed to optimize an iSCSI storage solution consisting of just a single device, and not optimal for a SAN of multiple arrays):

switch(config)# no iscsi enable

Enabling the PortFast Option to Configure STP Edge Ports:

switch(config)# spanning-tree mode rstp

switch(config)# interface ethernet g10

switch(config-if)# spanning-tree portfast

Configuring Flow Control (and speed and duplex settings):

switch(config)# interface range ethernet g(1-48)

switch(config-if)# speed 1000

switch(config-if)# duplex full

switch(config-if)# flowcontrol on

Disabling port storm control on one port:

switch(config)# interface ethernet g1

switch(config-if)# no port storm-control broadcast enable

Disabling port storm control on all ports:

switch(config)# interface range ethernet all

switch(config-if)# no port storm-control broadcast enable

Enabling Jumbo Frames (on all ports):

switch(config)# port jumbo-frame

PowerConnect 62xx Switch Configuration – CLI Commands

Note the different naming convention!

Enabling the PortFast Option to Configure STP Edge Ports:

switch(config)# spanning-tree mode rstp

switch(config)# interface ethernet 1/g10

switch(config-if)# spanning-tree portfast

Configuring Flow Control – enabling on all ports:

switch(config)# flowcontrol

Disabling port storm control:

switch(config)# interface ethernet 3/g10

switch(config-if)# no storm-control unicast

Disabling port storm control on all ports:

switch(config)# interface range ethernet all

switch(config-if)# no storm-control unicast

Enabling Jumbo Frames (on all ports):

switch(config)# interface range ethernet all

switch(config-if)# mtu 9216

Cisco IOS Based Switch Configuration – CLI Commands

Enabling privileged mode and entering configuration mode:

CiscoSW> enable

CiscoSW# configure terminal

CiscoSW(config)#

Enabling the PortFast Option to Configure STP Edge Ports:

CiscoSW(config)# interface gi1/0/1

CiscoSW(config-if)# spanning-tree portfast

Enabling the PortFast Option globally:

CiscoSW(config)# spanning-tree portfast default

Configuring Flow Control:

CiscoSW(config)# interface gigabitethernet1/0/1

CiscoSW(config-if)# flowcontrol receive desired

Disabling Unicast Storm Control:

CiscoSW(config)# interface gigabitethernet1/0/15

CiscoSW(config-if)# no storm-control unicast level

Enabling Jumbo Frames (requires switch reload):

CiscoSW(config)# system mtu jumbo 9000

CiscoSW(config)# exit

CiscoSW(config)# copy running-config startup-config

CiscoSW(config)# reload

… next to enable an individual VLAN to use Jumbo Frames (Note – VLAN1 cannot have Jumbo Frames enabled):

CiscoSW# vlan database

CiscoSW(vlan)# vlan 2 mtu 9000