Intel 82599: Port Identification Does Not Blink the LED on Linux

Case background

On a server with several NICs, the customer needed to map Linux interface names to physical ports. ethtool -p <interface> blinked the onboard Gigabit port but did not light the Intel 82599 port.

Scope of the finding

The vendor attributes the failure in that environment to lack of support for LED identification. This does not establish that all 82599 adapters or all ixgbe driver versions lack ethtool -p support; Intel’s driver includes physical-identification LED handling, subject to the adapter’s supported operations.

Source workaround

The case used the diagnostic self-test below and observed the port LED turn on, blink and then turn off over approximately five seconds:

ethtool -t <interface>

Service interruption: This is a NIC diagnostic test, not an equivalent non-disruptive LED-location command. The source warns that it interrupts the network. Do not run it on an interface carrying active production traffic; arrange an appropriate maintenance window and independent access before using the case workaround. Duration and LED behavior can differ by adapter and driver.