Howto: Linux see new fiber channel attached disk LUNs without rebooting

To see new Fiber Channel attached disk LUNs (Logical Unit Numbers) on a Linux system without rebooting, you can use the "rescan-scsi-bus.sh" script or the "lsscsi" command.

The "rescan-scsi-bus.sh" script is a utility that is included with the "sg3_utils" package, which is available on most Linux distributions. To use the script, follow these steps:

1. Install the "sg3_utils" package using your distribution's package manager. For example:

sudo apt install sg3-utils (Debian/Ubuntu)
sudo yum install sg3_utils (Red Hat/CentOS)
sudo dnf install sg3_utils (Fedora)

2. Run the "rescan-scsi-bus.sh" script as root or using "sudo". For example:

sudo rescan-scsi-bus.sh -l

This will scan the SCSI bus and list any new LUNs that have been added.

Alternatively, you can use the "lsscsi" command to list the SCSI devices on the system, including LUNs. For example:

lsscsi -g

This will list all SCSI devices on the system, along with their vendor, model, and LUN ID. You can use this command to see if any new LUNs have been added to the system.

Keep in mind that these commands may not work if the SCSI driver or kernel module for your Fiber Channel adapter is not loaded or is not compatible with your Linux distribution.