To configure the newly added LUNS on RHEL:

To configure the newly added LUNS on RHEL:


# ls /sys/class/fc_host

host0 host1 host2 host3

fdisk -l 2>/dev/null | egrep '^Disk' | egrep -v 'dm-' | wc -l

echo "1" > /sys/class/fc_host/host0/issue_lip

echo "- - -" > /sys/class/scsi_host/host0/scan

echo "1" > /sys/class/fc_host/host1/issue_lip

echo "- - -" > /sys/class/scsi_host/host1/scan

echo "1" > /sys/class/fc_host/host2/issue_lip

echo "- - -" > /sys/class/scsi_host/host2/scan

echo "1" > /sys/class/fc_host/host3/issue_lip

echo "- - -" > /sys/class/scsi_host/host3/scan

cat /proc/scsi/scsi | egrep -i 'Host:' | wc -l

fdisk -l 2>/dev/null | egrep '^Disk' | egrep -v 'dm-' | wc -l


Alternatively, we can
run the re-scan-scsi script.

To scan new LUNs on Linux operating system which is using QLogic driver

You need to find out driver proc file /proc/scsi/qlaXXX.

For example on my system it is /proc/scsi/qla2300/0

Once file is identified you need to type following command (login as the root):



# echo "scsi-qlascan" > /proc/scsi/qla2300/0
# cat /proc/scsi/qla2300/0


Now use the script rescan-scsi-bus.sh new LUN as a device. Run script as follows:



# ./rescan-scsi-bus.sh -l -w


The output of ls -l /sys/block/*/device should give you an idea about how each device is connected to the system.


Thanks & Reference: http://lazysystemadmin.blogspot.com/2010/06/scan-and-configure-new-luns-on-redhat.html