venkat25_1
It seems that you've been having device issues for 3 weeks now, right?
https://vox.veritas.com/t5/NetBackup/Re-tape-drive-shows-active-but-the-ready-column-shows-NO/m-p/867468
Your screenshot shows that the OS only sees one tape drive.
Do you see the library in Device Manager under 'Medium Changer'?
As an application, NetBackup has no direct access to a device, instead relying on the operating system (OS) to handle any communication with the device.
Any troubleshooting should therefore start at the OS level.
As per the TN that I shared in your other post:
If the Tape Drives do not appear (in Device Manager), the operating system is not able to detect the devices. Begin by rebooting the server in question and see if the operating system can detect the devices when it comes back up. In addition, review the Event Viewer Application and System logs to try and determine what event resulted in the drives being lost. If on reboot, the drives are still not shown in Device monitor, further hardware troubleshooting is required. Review the cabling, SCSI controllers, HBA cards, or the drives themselves for any problems or errors.
Consult the hardware vendor and operating system vendor for assistance.