11
IT organizations can also leverage the Emulex Virtual HBA technology, based on the ANSI T11 N_Port ID
Virtualization (NPIV) standard. This virtualization technology allows a single physical CNA or HBA port to
function as multiple virtual ports (VPorts), with each VPort having a separate identity in the Fabric.
NPIV support began with ESX Server 3.5 and requires use of RDM. Using NPIV, each virtual machine can
attach to its own VPort which consists of the combination of a distinct Worldwide Node Name (WWNN)
and multiple Worldwide Port Names (WWPNs), as shown in Figure 10. Again, the procedures for using this
technology are the same as those for Fibre Channel HBAs, including full support for virtual machine and
virtual port migration by VMotion.
Configuring the LP21000 for Multipathing in ESX
Multipathing is common technology used by data centers to protect against adapter, switch, or cable failure.
Enabling multipathing with the CNA typically means providing link redundancy either in the form of dual-
port configurations or a configuration with two single port CNAs to support failover. Similar to HBA
multipath configuration, each of the CNA ports used for multipathing must have visibility to the same LUNs
including proper physical connectivity, LUN masking, zoning, and any other array configuration. When each
LP21000 has the required visibility to the same LUNs and an ESX data store has been appropriately created
on those LUNs, then ESX will provide the path switching or the multipathing to that data store, providing a
redundant path for VMs to their corresponding storage store. No special drivers are required, since the
multipathing functionality is part of ESX.
A single dual-port CNA can provide port redundancy with each port connecting to a different CEE switch.
Though the above setup provides multiple data paths to the storage and provides active-standby links for
networking, it does not eliminate the CNA as the single point of failure. This situation is avoided by the next
configuration. Added redundancy can be provided with two CNAs serving one host. Installing two CNAs in
one host is the recommended configuration for high availability converged networking.
Server w/
LP21002
FCoE Enabled
Switch
FCoE Enabled
Switch
SAN A
SAN B
Figure 10: Port level redundancy using a single Dual-Ported CNA