Configuring SCSI devices

SUSE Linux Enterprise Server 15 SP5 LPAR mode z/VM guest

FCP devices that use NPIV mode detect the LUNs automatically and no configuring is necessary. If needed, configure the LUN manually.

For each FCP device that uses NPIV mode and if you did not disable automatic LUN scanning, the LUNs are configured for you. In this case, no FCP LUN entries are created under /sys/bus/ccw/drivers/zfcp/<device_bus_id>/<wwpn>.

To find out whether an FCP device is using NPIV mode, check the port_type attribute. For example:

# cat /sys/bus/ccw/drivers/zfcp/0.0.1901/host*/fc_host/host*/port_type
NPIV VPORT

To find out whether automatic LUN scanning is enabled, check the current setting of the module parameter zfcp.allow_lun_scan. The example below shows automatic LUN scanning as turned on.

# cat /sys/module/zfcp/parameters/allow_lun_scan
Y

Important: Configuration changes can directly or indirectly affect information that is required to mount the root file system. Such changes require an update of the initrd of both the auxiliary kernel and the target kernel, followed by a re-write of the boot record (see Rebuilding the initial RAM disk image).