10-01-2012 03:24 PM
Solved! Go to Solution.
10-01-2012 04:00 PM
Why don't you run the commands and find out ?
However, as you have made an effort to find the answer, I will assist.
cat /proc/scsi/scsi shows what the Linux os can see (devices)
scan does NOT detect devices at the os level.
It sends a scsi command to any device already detected by the operating system. This is not the same as detecting the devices at the os level. For the scan comand to work, the os must have already discovered the devices.
So, scan will show the devices detected, but is does not detect them itself.
Martin
10-01-2012 04:00 PM
Why don't you run the commands and find out ?
However, as you have made an effort to find the answer, I will assist.
cat /proc/scsi/scsi shows what the Linux os can see (devices)
scan does NOT detect devices at the os level.
It sends a scsi command to any device already detected by the operating system. This is not the same as detecting the devices at the os level. For the scan comand to work, the os must have already discovered the devices.
So, scan will show the devices detected, but is does not detect them itself.
Martin
10-01-2012 04:02 PM
10-01-2012 04:05 PM
cat /proc/scsi/scsi shows what the Linux os can see (devices)
scan does NOT detect devices at the os level.
It sends a scsi command to any device already detected by the operating system. This is not the same as detecting the devices at the os level. For the scan comand to work, the os must have already discovered the devices.
So, scan will show the devices detected, but is does not detect them itself.
What it means that it sends a scsi command to any device?
Does it check the physical connectivity?
10-01-2012 04:24 PM
scsi commands are commands sent to 'scsi' devices that make them do things.
This is a command that sends a scsi command, using the -d option is sends a 'scsi inquiry' command that makes a scsi device respond with information about itself.
Inquiry data: removable dev type 1h HP DAT72X6 B604
10-01-2012 06:23 PM
Can i say scan command is what netbackup can see via the Operating System.?
10-01-2012 08:58 PM
100% correct.
The commands that you ran above was done on a machine where no devices are attached.
scan just showed headings and no devices.
cat /proc/scsi/scsi showed no output.
If you do the same on a system where devices are attached, you will see different output.