Dell ISCSI manual Network Configuration Recommendations

Network Configuration Recommendations

It is recommended that you follow the guidelines in this section. In addition to these guidelines, all the usual rules for proper network configuration apply to group members.

Recommendation	Description
Network connections between	Connect array(s) and hosts to a switched network and ensure that all network
array(s) and hosts	connections between hosts and array(s) are Gigabit or 10 Gigabit Ethernet.
A reliable and adequately sized	For effective and predictable replication, ensure that the network link between the
network link for replication	primary and secondary groups is reliable and provides sufficient bandwidth for
	copying data.

No Spanning-Tree Protocol (STP) functionality on switch ports that connect end nodes

Connectivity between switches

Do not use STP on switch ports that connect end nodes (iSCSI initiators or storage array network interfaces). However, if you want to use STP or Rapid Spanning-Tree Protocol (RSTP) (preferable to STP), enable the port settings available on some switches that let the port immediately transition into STP forwarding state upon link up. This functionality can reduce network interruptions that occur when devices restart and should only be enabled on switch ports that connect end nodes.

NOTE: It is recommended that you use Spanning-Tree and trunking for multi- cable connections between switches.

The iSCSI switches must be connected together. Use stacking ports or port trunking to create a high-bandwidth link between the switches. If a single non-stacking link is used, it can become the bottle-neck and negatively affect the performance of the storage system.

Enable Flow Control on	Enable Flow Control on each switch port and NIC that handles iSCSI traffic. Dell
switches and NICs	EqualLogic PS Series arrays correctly respond to Flow Control.
Disable Unicast storm control	Disable Unicast storm control on each switch that handles iSCSI traffic, if the switch
on switches	provides this feature. However, the use of broadcast and multicast storm control is
	encouraged on switches.
Enable Jumbo Frames on	Enable Jumbo Frames on each switch and NIC that handles iSCSI traffic to obtain
switches and NICs	performance benefit and ensure consistent behavior.
Disable iSCSI Optimization on	Disable iSCSI Optimization, if the switch provides this feature, to avoid blocking
switches	internal communication between the array members.

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