Iscsi Connections For Asynchronous Mirroring; Fibre Channel Configurations Overview - Quantum StorNext QD7000 Hardware Manual

136 | Hardware Cabling Guide

iSCSI connections for Asynchronous Mirroring

You can use iSCSI connections for the Asynchronous Mirroring feature. Connect one iSCSI port on
each controller of the local (primary) storage array to the corresponding controller on the remote
(secondary) storage array. You can make connections through a switched fabric or directly between
controllers. During asynchronous mirror group creation, the source storage array attempts to connect
to the target storage array. The source storage array scans the IPv4 iSCSI ports in order until it finds a
connection. If the source storage array fails to find an IPv4 connection, it repeats the process using
IPv6.
To improve performance, connect the lowest numbered iSCSI port on each controller of the
Note:
local storage array to the corresponding controller on the remote storage array. This reduces delay
in asynchronous mirror group creation.
Note: Make sure that Internet Control Message Protocol (ICMP) response is enabled on storage
arrays used with the Asynchronous Mirroring feature. See the SANtricity online help topic "Set
Storage Array ICMP Response."

Fibre Channel configurations overview

Because of possible restrictions at the host level, the supported Synchronous Mirroring and
Asynchronous Mirroring configurations contain Fibre Channel switches. These Fibre Channel
switches are zoned so that a single host adapter can access only one controller per storage array.
Additionally, all configurations use a separate zone for the ports that are reserved for the
Synchronous Mirroring feature or the Asynchronous Mirroring feature.
Note: You cannot use the base Fibre Channel ports on an E5400 controller-drive tray or a EF540
flash array to make a connection for Asynchronous Mirroring if the controller-drive tray uses an
InfiniBand host interface card for host connections.
Do not zone the uplink port (E_port) that connects (cascades) switches within a fabric.
Note:
Switch zoning configurations are typically set up by using the switch management software that is
provided by the manufacturer of the Fibre Channel switch. This software should have been included
with the materials that are provided when the switch was purchased.
When two or more Fibre Channel switches are cascaded together, the switch management software
combines the ports for all of the switches that are linked. For example, if two 16-port Fibre Channel
switches are cascaded with a physical connection using a Fibre Channel cable, the switch
management software shows ports 0 through 31 participating in the fabric rather than two switches
each with ports 0 through 15. Therefore, a zone that is created containing any of these ports can exist
on multiple cascaded switches.
The following figure shows both cascaded and non-cascaded switches. The top-half of the figure
shows a set of cascaded switches that are on the same network. Therefore, Zone 1 is the same zone
on Switch 1A as Zone 1 is on Switch 1B. In a single-mode Fibre Channel environment, the two
switches are connected by a single port on each switch that is designated as an E_port, which is not
in a zone.
The set of switches in the bottom half of the following figure is on the same network but is not
cascaded. Although both sets contain a Zone 1 (shown as Zone A in Switch 2), these zones are
independent of each other.