Step 5: Configuring the zfcp device driver

FCP setups running in NPIV mode detect the LUNs automatically and after setting the device online. No further configuration is necessary.

Procedure

NPIV example
1. To set FCP device 0.0.5400 online, issue the following command:
```
# chccwdev --online 0.0.5400
Setting device 0.0.5400 online
Done
```
  The chccwdev command is part of s390-tools. For a description of the command see Device Drivers, Features, and Commands, SC33-8411.
  After setting the FCP device online, all LUNs with valid host-connections for the WWPN of the NPIV FCP device are automatically visible as SCSI devices:
```
# lsscsi
[0:0:0:1073758410]disk IBM 2107900 0.33 /dev/sda
[0:0:0:1073823946]disk IBM 2107900 0.33 /dev/sdb
```
2. To find out if the FCP setup is running in NPIV mode, check the port_type attribute of the FCP device, for example:
```
# cat /sys/bus/ccw/drivers/zfcp/0.0.5400/host0/fc_host/host0/port_type
NPIV VPORT
```
Non-NPIV example
1. To set the non-NPIV FCP device 0.0.54ea online, issue the following command:
```
# chccwdev --online 0.0.54ea
Setting device 0.0.54ea online
Done
```
2. To configure a LUN 0x4010403200000000, issue the following command:
```
# cd /sys/bus/ccw/drivers/zfcp/0.0.54ea
# echo 0x4010403200000000 > 0x500507630303c562/unit_add
```
  If the port and the LUN specify a disk in a storage subsystem you should now see a new SCSI disk:
```
# lsscsi
[0:0:0:0] disk IBM 2107900 .309 /dev/sda
# lszfcp -D
0.0.5400/0x500507630303c562/0x4010403200000000 0:0:0:0
```
  The lszfcp command is part of s390-tools. For a description of the command see Device Drivers, Features, and Commands, SC33-8411

Now the device, for example /dev/sda, can be used. In our example the disk can be formatted and mounted.

To format a SCSI disk, issue:
```
# fdisk /dev/sda
... 
```
To generate a file system, issue:
```
# mke2fs -j /dev/sda1 
```
To mount partition 1 of the SCSI disk, issue:
```
# mount -t ext3 /dev/sda1 /mnt
```