ThinkSystem SN850 - Compute node controls, connectors, and LEDs

Use this information for details about the controls, connectors, and LEDs.

The following illustration identifies the buttons, connectors, and LEDs on the control panel.

Figure 1. Compute node control panel buttons, connectors, and LEDs

Table 1. Compute node control panel buttons, connectors, and LEDs
`1` USB 3.2 Gen 1 connector	`6` Drive status LED (yellow)
`2` KVM connector	`7` Power button/LED (green)
`3` Drive activity LED (green)	`8` Identification LED (blue)
`4` Drive status LED (yellow)	`9` Fault LED (yellow)
`5` Drive activity LED (green)	`10` USB management button

1 USB connector

Connect a USB device to this USB 3.2 Gen 1 connector.

It is best practice to connect a USB device to the front of only one compute node at a time in each Flex System chassis.

2 KVM connector

Connect the KVM cable to this connector (see KVM cable for more information).

It is best practice to connect the KVM cable to only one compute node at a time in each Flex System chassis.

3 5 Drive activity LED (green)

Green LEDs are on all hot-swap drives. When this green LED is lit, it indicates that there is activity on the associated hard disk drive or solid-state drive.

When this LED is flashing, it indicates that the drive is actively reading or writing data.
For all types of drive, this LED is solid on when the drive is powered but not active.
The drive activity LED might be in a different location on the front of the drive, depending on the drive type that is installed.

4 6 Drive status LED (yellow)

The state of this yellow LED indicates an error condition or the RAID status of the associated hard disk drive or solid-state drive:

When the yellow LED is lit continuously, it indicates that an error has occurred with the associated drive. The LED turns off only after the error is corrected. You can check the CMM event log to determine the source of the condition.
When the yellow LED flashes slowly (one time per second), it indicates that the associated drive is being rebuilt.
When the yellow LED flashes rapidly (four times per second), it indicates that the associated drive is being located.
The drive status LED might be in a different location on the front of the drive, depending on the drive type that is installed.

7 Power button/LED (green)

When the compute node is connected to power through the Flex System chassis, press this button to turn on or turn off the compute node.

For more information about the CMM power command, see Flex System Chassis Management Module: Command-Line Interface Reference Guide.

Note: The power button works only if local power control is enabled for the compute node. Local power control is enabled and disabled through the CMM power command and the CMM web interface.

After the compute node is removed from the chassis, press and hold this button to activate the system-board LEDs and light path diagnostics. See the Viewing the light path diagnostics LEDs for more information.

This button is also the power LED. This green LED indicates the power status of the compute node:

Flashing rapidly: The LED flashes rapidly (four times per second) for one of the following reasons:
- The compute node has been installed in a powered chassis. When you install the compute node, the LED flashes rapidly while the XClarity Controller in the compute node is initializing and synchronizing with the Chassis Management Module. The time required for a compute node to initialize varies by system configuration.
- Power permissions have not been assigned to the compute node through the Chassis Management Module.
- The Flex System chassis does not have enough power to turn on the compute node.
- The XClarity Controller in the compute node is not communicating with the Chassis Management Module.
The power LED blink rate slows when the compute node is ready to be turned on.
Flashing slowly: The LED flashes slowly (one time per second) means the compute node is connected to power through the Flex System chassis and is ready to be turned on.
Lit continuously: The compute node is connected to power through the Flex System chassis and is turned on.

When the compute node is on, pressing this button causes an orderly shutdown of the compute node so that it can be removed safely from the chassis. This includes shutting down the operating system (if possible) and removing power from the compute node.

Attention: If an operating system is running, you might have to press the button for approximately 4 seconds to initiate the shutdown. This forces the operating system to shut down immediately. Data loss is possible.

8 Identification LED (blue)

The system administrator can remotely light this blue LED to aid in visually locating the compute node. When this LED is lit, the identification LED on the Flex System chassis is also lit. The identification LED can be lit and turned off through the CMM led command, the CMM web interface and the Lenovo XClarity Administrator application (if installed).

There are four states of identification LED:

Table 2. Identification LED state
LED state	Operation required for this state	Description
Off	This is the default state, no operation required	Compute node is in the normal state.
Solid On	Press USB management button Use CMM or Lenovo XClarity Controller	Compute node is in locally manual operation status. To return LED to Off state, press USB management button again or change state through CMM or Lenovo XClarity Controller.
Blinking (blink one time per second)	Use CMM or Lenovo XClarity Controller	Compute node is in the locally manual operation status (same as solid On state). To return LED to Off state, press USB management button again or change state through CMM or Lenovo XClarity Controller.
Slow blinking (blink one time every two seconds)	Press USB management button for 3 seconds Use CMM or Lenovo XClarity Controller	Compute node is in the status, where USB port is connected to the Lenovo XClarity Controller. In this state, you can access the Lenovo XClarity Controller directly via a mobile device connected to the USB connector of the compute node. To return LED to Off state, press USB management button again or change state through CMM or Lenovo XClarity Controller.

For more information about the CMM led command, see the Flex System Chassis Management Module: Command-Line Interface Reference Guide.
From the CMM web interface, select Compute Nodes from the Chassis Management menu. For more information, see "Flex System Chassis Management Module: User's Guide". All fields and options are described in the CMM web interface online help.
For more information about the Lenovo XClarity Administrator application, see the Lenovo XClarity Administrator information page.

9 Fault LED (yellow)

When this yellow LED is lit, it indicates that a system error has occurred in the compute node. In addition, the fault LED on the chassis system LED panel is lit. You can check the CMM event log and the light path diagnostics LEDs to determine the source of the condition. See Light path diagnostics LEDs for more information about the LEDs on the compute node.

The fault LED turns off only after the error is corrected. When the fault LED turns off, you should also clear the XClarity Controller event log. Use the Setup utility to clear the XClarity Controller event log.

10 USB management button

Press the button and held for 3 seconds;to switch the USB 3.2 Gen 1 port between default mode and Lenovo XClarity Controller management mode.

Note:

It is best practice to connect a USB device to the front of only one compute node at a time in each Lenovo Flex System chassis.
When enabling the USB port for system management, do not insert USB 3.2 Gen 1 devices.