Considerations for iSCSI configurations overview

Contributors

You should consider several things when setting up your iSCSI configuration.

  • You can set up your iSCSI configuration with single nodes or with HA pairs.

    Direct connect or the use of Ethernet switches is supported for connectivity. You must create LIFs for both types of connectivity

  • You should configure one management LIF for every storage virtual machine (SVM) supporting SAN.

  • Selective LUN mapping (SLM) limits the paths that are being utilized in accessing the LUNs owned by an HA pair.

    This is the default behavior for LUNs created with ONTAP releases.

  • HA pairs are defined as the reporting nodes for the Active/Optimized and the Active/Unoptimized paths that will be used by the host in accessing the LUNs through ALUA.

  • It is recommended that all SVMs in ISCSI configurations have a minimum of two LIF’s per node in separate Ethernet networks for redundancy and MPIO across multiple paths.

  • You need to create one or more iSCSI paths from each node in an HA pair, using logical interfaces (LIFs) to allow access to LUNs that are serviced by the HA pair.

    If a node fails, LIFs do not migrate or assume the IP addresses of the failed partner node. Instead, the MPIO software, using ALUA on the host, is responsible for selecting the appropriate paths for LUN access through LIFs.

  • VLANs offer specific benefits, such as increased security and improved network reliability that you might want to leverage in iSCSI.