A host system is a computer that is connected to the system through supported connection protocols. The system supports host connections through Fibre Channel interface, serial-attached SCSI (SAS) connections, or an IP network. To use Fibre Channel or Fibre Channel over Ethernet connections to a storage area network (SAN), an optional host interface adapter must be installed.
A host object is a logical object that represents a list of worldwide port names (WWPNs), NVMe qualified names (NQNs), or iSCSI names that identify the interfaces that the host system uses to communicate with the system. Fibre Channel and SAS connections use WWPNs to identify host interfaces to the system. iSCSI names can be either iSCSI qualified names (IQNs) or extended unique identifiers (EUIs). NQNs are used to identify hosts that use NVMe over Fibre Channel connections. Only certain models of the system support NVMe over Fibre Channel connections. Verify your system hardware before configuring hosts connection with this protocol.
The SAS host ports on Lenovo Storage V series node canisters can operate at 6 Gbps or 12 Gbps. The Lenovo Storage V3700 V2 XP system has two onboard 12 Gbps host attachment SAS ports. Lenovo Storage V3700 V2 XP systems can also support the optional SAS host interface adapter.Lenovo Storage V3700 V2, Lenovo Storage V5030, and Lenovo Storage V5030F systems support 12 Gbps SAS host attachment I/O but must have the optional host interface adapter installed. These models require different cables based on the speeds. If you want to run 12 Gbps SAS, you need to use a 12 Gbps cable.
A typical configuration has one host object for each host system that is attached to the system. If a cluster of hosts accesses the same storage, you can add the hosts into a host cluster object to make configuration simpler.
When you create a new Fibre Channel host object, the system presents a list of candidate WWPNs that have been logged into the system but are not yet configured in host objects. Some Fibre Channel HBA device drivers do not leave their ports logged in if no disks are detected on the fabric, so they are not visible in the list of candidate ports. You must enter the WWPNs for such hosts manually.There is no equivalent list of candidate IQNs available when creating iSCSI hosts. All iSCSI host port IQNs must be entered manually.
The system can detect only WWPNs that have connected to the system through the Fibre Channel network or through any IP network. Some Fibre Channel HBA device drivers do not leave ports logged in if no disks are detected on the fabric or IP network.The system can detect only WWPNs that have connected to the system through the Fibre Channel network, SAS network, or through any IP network. Some Fibre Channel HBA device drivers do not leave ports logged in if no disks are detected on the fabric or IP network. The configuration interface provides a method to manually type the port names.
The system does not automatically present volumes to the host system. You must map each volume to a particular host object to enable the volume to be accessed through the either WWPNs or iSCSI names that are associated with the host object.For Fibre Channel, NVMe over Fibre Channel, and SAS-attached hosts, the system reports the node login count, which is the number of nodes that can detect each WWPN. If the count is less than expected for the current configuration, you might have a connectivity problem. To view potential connectivity issues for Fibre Channel-attached hosts in the management GUI, select or use the lsfabric command. To view connectivity issues for NVMe over Fibre Channel attached hosts in the manage, select or use the lsnvmefabric command.For iSCSI-attached hosts, the number of logged-in nodes refers to iSCSI sessions that are created between hosts and nodes, and might be greater than the current number of nodes on the system.You can display the login information for each host in the management GUI to determine which ports for the logged-in nodes are connected to the Ethernet-attached hosts. To display this information, select and right-click the host and select IP Login Information. To view login information in the command-line interface, use the lshostiplogin to list login session details for a specified host that is logged into a configured Ethernet port on the system. This information can be used to detect connectivity issues between the system and hosts and to improve the configuration of hosts to improve performance.
You can use the port-mask property of the host object to control the Fibre Channel ports on each system node that a host can access. The port mask applies to logins from the WWPNs that are associated with the host object. The port-mask configuration has no effect on iSCSI connections.
For each login between a host Fibre Channel port and node Fibre Channel port, the node examines the port mask for the associated host object and determines if access is allowed or denied. If access is denied, the node responds to SCSI commands as if the HBA WWPN is unknown.
The port mask is 64 bits. Valid mask values range from all 0s (no ports enabled) to all 1s (all ports enabled). For example, a mask of 0011 enables port 1 and port 2. The default value is all 1s.
When you create a host mapping to a host, the host ports that are associated with the host object can view the LUN that represents the volume on many ports. Nodes follow the American National Standards Institute (ANSI) Fibre Channel (FC) standards for SCSI LUs that are accessed through multiple node ports. All nodes within a single I/O group present a consistent set of SCSI LUs across all ports on those nodes.