How to check mounted luns ?

Install FC PCI card on server.


To check the FC PCI card port details on Server. use below commnd.

#ls /sys/class/fc_host
 host8  host9
(In above case host8 and host9 are adapters )

# cat /sys/class/fc_host/host8/port_name
0x2100001b328a5ec4
# cat /sys/class/fc_host/host9/port_name
0x2101001b32aa5ec4
 (In above example we have 2 port on server.. With wwnn number as described in output)
You can also get above information using command below
#systool -c fc_host -A port_name


------------------------------------------------------------------------
 Before scanning the fc lun  . 
Check the number of disks
# fdisk -l 2>/dev/null | egrep '^Disk' | egrep -v 'dm-' | wc -l
5
(In above case i have  5 disks before running the scan)
 
# echo "1" > /sys/class/fc_host/host8/issue_lip
# echo "1" > /sys/class/fc_host/host9/issue_lip

(Check /var/log/messages .. Sometime it may take time as its asynchronous process )
After scanning the fc lun.
Check the number of disks.
# fdisk -l 2>/dev/null | egrep '^Disk' | egrep -v 'dm-' | wc -l
9
(Earlier it was 5 .. We have added only one lun however due to fc adaptor's 4 port its showing 4.. We need to enable multi pathing here)
You can also ensure the above by counting the number of disks.
#fdisk -l |egrep '^Disk' |egrep -v 'dm-' ( some disks excluded to include new disk details)
In addition to existing disks i can see below 4 disks
Disk /dev/sdf: 1099.5 GB, 1099511627776 bytes
Disk /dev/sdg: 1099.5 GB, 1099511627776 bytes
Disk /dev/sdh: 1099.5 GB, 1099511627776 bytes
Disk /dev/sdi: 1099.5 GB, 1099511627776 bytes

All the lun details are stored in below path.
/dev/disk/by-path

Here comes the pain understanding the output :)