Dell E21S001, R820 owner manual NIC Indicator Codes, Indicators are off Link indicator is

Item	Indicator, Button, or	Icon	Description
	Connector
8	System identification		Allows you to connect the optional system status indicator
	connector		assembly through the optional cable management arm.
9	System identification button		The identification buttons on the front and back panels
			can be used to locate a particular system within a rack.
			When one of these buttons is pressed, the LCD panel on
			the front and the system status indicator on the back
			flashes until one of the buttons is pressed again.
			Press to toggle the system ID on and off. If the system
			stops responding during POST, press and hold the system
			ID button for more than five seconds to enter BIOS
			progress mode.
			To reset the iDRAC (if not disabled in F2 iDRAC setup)
			press and hold the button for more than 15 seconds.
10	Power supply (PSU1)		AC	750 W or 1100 W
			Or
			DC	1100 W (when available)
11	PCIe expansion card slots		Allows you to connect a PCI Express expansion card.
	(2)
12	Power supply (PSU2)		AC	750 W or 1100 W
			Or
			DC	1100 W (when available)

NIC Indicator Codes

Figure 5. NIC Indicator
1.	link indicator	2.	activity indicator
Indicator		Indicator Code
Link and activity		The NIC is not connected to the network.
indicators are off
Link indicator is		The NIC is connected to a valid network at its maximum port speed (1 Gbps or 10 Gbps).
green

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