Does ONTAP support both FC and iSCSI paths to the same LUN from the same windows server?
Applies to
- ONTAP 9
- Windows
Answer
The Data ONTAP DSM supports both FC and iSCSI paths to the same LUN for clustered Data ONTAP.
The DSM does not support both FC and iSCSI paths to the same LUN for Data ONTAP operating in 7-Mode. Because ALUA is required for FC paths, and ALUA is not supported for iSCSI paths to 7-Mode LUNs. All paths must have the same ALUA setting. But can still have FC paths to some 7-Mode LUNs and iSCSI paths to other 7-Mode LUNs.
For the Windows native DSM, Since MPIO occurs above the Miniport driver layer, the MPIO driver only sees SCSI devices and does not know about the transport protocol. This allows Fibre Channel and iSCSI paths to the same LUN to be mixed. Since the protocols have different access characteristics and performance, we recommend that, if they are mixed, they are used in an active-passive configuration in which one takes over if the other fails.
All in all, ONTAP supports both FC and iSCSI paths to the same LUN for clustered Data ONTAP. If it is from the different hosts, that need the host level cluster to manage the LUN file system consistently like Windows Cluster. If it is from the same host, safely contact the Host OS support to double confirm the multipath software support or not for this behavior.
Note: FC refers to traditional Fibre Channel and Fibre Channel over Ethernet (FCoE).
Additional Information