6.5.1

Table Of Contents
The iSCSI adapter and physical NIC connect through a virtual VMkernel adapter, also called the virtual
network adapter or the VMkernel port. You create a VMkernel adapter (vmk) on a vSphere switch
(vSwitch) using 1:1 mapping between each virtual and physical network adapter.
One way to achieve the 1:1 mapping when you have multiple NICs, is to designate a separate vSphere
switch for each virtual-to-physical adapter pair.
Note If you use separate vSphere switches, you must connect them to different IP subnets. Otherwise,
VMkernel adapters might experience connectivity problems and the host fails to discover the iSCSI LUNs.
The following examples show configurations that use vSphere standard switches, but you can use
distributed switches as well. For more information about vSphere distributed switches, see the vSphere
Networking documentation.
Figure 112. 1:1 Adapter Mapping on Separate vSphere Standard Switches
VMkernel adapters
Physical adapters
vmnic1
iSCSI1
vmk1
vSwitch1
VMkernel adapters
Physical adapters
vmnic2
iSCSI2
vmk2
vSwitch2
An alternative is to add all NICs and VMkernel adapters to a single vSphere standard switch. In this case,
you must override the default network setup and make sure that each VMkernel adapter maps to only one
corresponding active physical adapter.
Note If the VMkernel adapters are on the same subnet, use the single vSwitch configuration.
Figure 113. 1:1 Adapter Mapping on a Single vSphere Standard Switch
VMkernel adapters
Physical adapters
vmnic2
vmnic1
iSCSI2
vmk2
iSCSI1
vmk1
vSwitch1
The following table summarizes the iSCSI networking configuration discussed in this topic.
vSphere Storage
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