Only Eight Fibre Channel Devices Detected When More than Eight Devices Are Assigned to the RedHat 5.5 Server

Publication Date:  2013-06-13 Views:  767 Downloads:  0
Issue Description
Product and version information:
 VTL3500 V100R002
 VTL6000 V100R003
 VTL6900 V100R005
Three tape libraries are created on the VTL, and two tape drives are assigned to each tape library. The three tape libraries are assigned to the backup server on which the RedHat 5.5 is installed. Then the VTL is restarted. The nine devices (including the three tape libraries and six drives) are all detected on the backup server. However, after being restarted, the backup server only detects eight Fibre Channel devices.
Alarm Information
Handling Process
Step 1 Log in to the backup server by using the PuTTY or SSH tool.
Step 2 Run cat /proc/scsi/scsi to check information about the connected Fibre Channel devices.
Step 3 Run echo “scsi add-single-device 0 0 0 8” > /proc/scsi/scsi to scan for SCSI devices.
Step 4 Run cat /proc/scsi/scsi again to check information about the connected Fibre Channel devices.
If the following command output is displayed, the devices are correctly displayed.

Step 5 Run vi /etc/rc.local to open the system boot file. Add the commands shown in the following red box to the file. These commands add corresponding LUNs to the system.
The commands added to the system boot file will be automatically executed upon the system start. The number 0 0 0 8 in the following figure indicates the corresponding LUN's number.

Root Cause
The RedHat 5.5 system only detects eight Fibre Channel devices when nine are assigned.