How to scan a new LUN added to Redhat linux server

Scan the new LUN in RHEL server.

Here echo command is used scan the newly added LUN in Linux server (RHEL)

SCSI_HOST

# echo "- - -" > /sys/class/scsi_host/hostx/scan

or

# echo "c t l" >  /sys/class/scsi_host/hostx/scan

FC_HOST

# echo "1" > /sys/class/fc_host/hostX/issue_lip
# echo "- - -" > /sys/class/scsi_host/hostx/scan

c   - channel on the HBA,
t   - SCSI target ID  ,
l   - LUN 
x   - HBA number

Hope it helps.