Install Guide

15 Citrix XenServer with Dell SC Series Storage Configuration and Deployment | 3132-CD-V
4.1 Open-iSCSI initiator setup with SC Series arrays
When planning an iSCSI network, isolate the iSCSI traffic from management traffic through the use of
separate switches and subnets. Failure to follow this best practice may result in compromised reliability or
performance.
When implementing multipathing with iSCSI storage, be certain none of the redundant iSCSI paths are
configured within the same subnet or on the same physical network as the management interface. If this
occurs, the iSCSI initiator will not be able to successfully establish a session over any iSCSI path on the
management network or subnet.
There are two commonly used ways to implement multipathing with the XenServer Open-iSCSI initiator to
connect to SC Series storage:
Multipath with dual subnets: In this configuration, the Front End iSCSI control ports on the SC Series
storage are on two separate subnets. This option uses MPIO for multipathing. This is the recommended
option when high availability (HA) is required.
Multipath with single subnet: In this configuration, the Front End iSCSI control ports on the SC Series
storage are on the same subnet. This option uses NIC bonding for path failover. This method is an optional
solution when the servers have a single iSCSI storage NIC and HA is not required.
4.2 Multipath with dual subnets
Using XenServer Open-iSCSI multipathing with dual subnets to properly connect to SC Series storage
requires the following:
 XenServer 6.5 or later
 iSCSI using two unique, dedicated storage NICs and subnets. The two subnets should be different
from the XenServer management network to comply with Citrix best practices
 Multipathing enabled on all XenServer hosts in the pool
 iSCSI target IP addresses for the SC Series storage Front End control ports. For the example
included in this document, the iSCSI FE control ports on SC Series storage are assigned IP
addresses 10.10.10.100/24 and 10.20.10.100/24
In this configuration, the SC Series storage is configured with the iSCSI Front End ports on two separate
subnets, different from the management interface. The SC Series storage is configured with two control ports,
one on each subnet. Multipathing is controlled through MPIO.