Allied Telesis AT-2911 Series Adapters - Manual (Page 107)

AT-2911 Series Gigabit Ethernet Network Adapters Installation and User’s Guide
107
Checking a Port LED on the Adapter
Each port has an LED that indicates the link status. The LED functions
once the driver is installed and the cables are connected properly. The
LED is lit is on if data traffic is present.
Before the port LED can provide troubleshooting information, the adapter
must be connected to the network and the network driver for your
particular operating system must be installed.
Before troubleshooting, verify the following:
 The adapter driver software has been installed.
 The adapter is connected to a network.
 The LED operates properly.
To check the LED status, see Table 1 on page 21.