Detect recently added vdisks in a VMware ESXi linux guest

After adding a vdisk to an ESXi linux guest you will assert that you can't find a new device in the running VM. You have to force a SCSI rescan.

1. find your host bus number with: grep mtpspi /sys/class/scsi_host/host?/proc_name
2. output should look like this: /sys/class/scsi_host/host2/proc_name:mptspi where the bold part is what you're searching for
3. force an SCSI rescan with echo "- - -" > /sys/class/scsi_host/<host>/scan and insert the host found in point two for <host>
4. cat /proc/scsi/scsi should now show the new added device