Patent ID: 8644185

Claim:
A system for network diagnosis, comprising: a library comprising a drive coupled to a network; an infusion device coupled to the network, wherein there is a portion of the network between the infusion device and the drive, the infusion device configured to infuse control data into the network at an infused data transfer rate, wherein infusing control data into the network comprises sending commands to the drive to write corresponding data to the drive; and a monitoring appliance coupled to the network and configured to send SCSI commands, including a first SCSI command and a second SCSI command subsequent to the first SCSI command, to the drive over the network when the control data is being transferred at the drive, wherein the monitoring appliance is further configured to calculate, for the infused control data, the data transfer rate of the infused control data at the drive based on comparing drive data returned in response to at least the first SCSI command and the second SCSI command to determine a measure of a network throughput for the portion of the network between the infusion device and the drive; wherein the first SCSI command comprises one of a Log Sense Command or an Inquiry Command and the second SCSI command comprises one of a Log Sense Command or an Inquiry Command.