How to Find HBA Card WWPN Address on Linux

We need “WWPN address” information of HBA card to create zoning on fiber channel switch to assign and unassign storage to a Linux host. There are two differnet methods to find “WWPN Address” on Linux depending upon RHEL Linux versions :

1. On Redhat Linux 5 and above . 
2. On Redhat 4 and below.

Now let’s see the two different methods to find “WWPN Address” on Linux depending upon RHEL Linux version

Method 1: On Redhat 5 and above (including OEL and CentOS),the/sys/class/scsi_host/host{n}/device/fc_host:host{n}/port_name file contains the HBA WWPN information.

Where n refers the number of HBA card available on the system . Please substitude n with either 0, 1, or 2 according to your system.

For example:

So from below output we can conclude there are two HBA Card on the system.

$ cd /sys/class/scsi_host/
$ ls
host0 host1

RHEL version is 5.3 as below output

$ cat /etc/redhat-release
Red Hat Enterprise Linux Server release 5.3 (Tikanga)

From below output  we got  the WWPN address of HBA host0

$ cat /sys/class/scsi_host/host1/device/fc_host:host0/port_name
0x10000000c9f2da9c

From below output  we got  the WWPN address of HBA host1

$ cat /sys/class/scsi_host/host1/device/fc_host:host1/port_name
0x10000000c9f2da9d

So we have got two “WWPN address” as for the system as below

0x10000000c9f2da9c
0x10000000c9f2da9d

Method 2: On Redhat 4 and below (including OEL and CentOS) , the /proc/scsi/[adapter-type]/[n] file contains the HBA WWPN information.

Where

adapter-type :It can be either qlaxxxx for QLogic adapters (or) lpfc for Emulex adapters.
n refers the number of HBA card available on the system . Please substitude n with either 0, 1, or 2 according to your system.