Led Indications And Diagnostics; Line Card And Pci Leds; Using Leds For Diagnostics - HP Cluster Platform Interconnects v2010 Manual

If you encounter any operational problems with your Myrinet system interconnect,
you can use the LEDs on each switch port and PCI interface to diagnose and correct
the problem. The monitoring line card installed on the system interconnect also
can be used for diagnostics. This chapter presents the following information:
• An explanation of the line card and PCI LEDs (Section 4.1).
• An explanation of how to use LEDs for diagnostic purposes (Section 4.2).
• An explanation of how to use the monitoring line card for diagnostics
(Section 4.3).

4.1 Line card and PCI LEDs

A line card in the Myrinet system interconnect has a Status LED, located on the
far left of each front panel. If the card is seated properly, the Status LED is green.
Each line card has eight ports. The LED on each port indicates the state of that
port. Green indicates the port is powered, and a link is connected. Yellow indicates
a fault. If the switch port is unlit, the switch is not powered, or there is a problem
with the line card. The LEDs for the ports only light when there is a fiber-optic
cable attached and the GM message passing system from Myrinet is running.
The monitoring line card has two LEDs. When it is locked in position, a green
LED illuminates. Another green LED illuminates when the monitoring line card
is connected to an Ethernet network.
The faceplate of each Myrinet PCI card in a server has two LEDs. A green LED
illuminates when the host is powered, the link is active, and the firmware is loaded
on the host. It blinks to show when packet traffic is flowing through the port. The
yellow LED pulses when there is packet-sending activity. Regular (heartbeat)
flashing indicates that the card is active, but there is no packet traffic over the
link. Irregular flashing at a higher rate indicates there is packet traffic on the link,
including the sending of acknowledgment packets in reply to packets received. The
rate of flashing is an indicator of the volume of traffic over the link. The yellow
LED is controlled by the RISC processor.

4.2 Using LEDs for diagnostics

Examine all components for illuminated link LEDs. If you do not see a link LED
illuminated on any component (either on the PCI card in the server or on a port on
a switch line card), use the following procedures to manually check the link:
1. If no green LEDs are illuminated, verify that the interconnect is powered on.
The interconnect powers on when rack power is applied. There is no separate
breaker on the interconnect chassis.
2. If a server's PCI interface port does not have a green link LED illuminated,
do the following:
a. Verify that the host is powered on and that there are no error LEDs
showing on the server's front panel. (Use the server's rear locator switch
to identify the server's front panel.)

LED indications and diagnostics

LED indications and diagnostics
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