Binding is the final stage of configuration to be done at the ESXi server to enable iSCSI multipathing. It refers to the process of associating existing VMkernel (vmk) interfaces to the software iSCSI adapter, thereby letting NMP manage multiple paths to the iSCSI targets.
Keep in mind that the iSCSI initiator and the iSCSI target should be in the same subnet. iSCSI port binding does not support routing.
The VMkernel interfaces should be first prepared with only one active and no standby adapters. This is discussed in detail in the Preparing the vSphere network for iSCSI multipathing recipe.
Once the VMkernel interfaces have been prepared, you could use the instructions in this recipe ...