Learn how to maximize Ethernet performance on your Mac.
For best networking results when using Ethernet, the Ethernet port which your Mac is connected to should be set to auto-negotiate. If you are not sure, ask your network administrator to verify this setting.
Important: Ethernet network connection issues may indicate that the network switch is not set to auto-negotiate. If a switch's port is not auto-negotiating, your computer detects the appropriate speed but defaults to half-duplex mode. If the switch's port at the other end of the link is configured for full-duplex, a large number of late events can occur on the link. If it isn't possible to set the switch to auto-negotiate, then set the switch's port to half-duplex. For more information, see the documentation that came with the Ethernet switch.
Note: If you connect your computer directly to a configurable Ethernet switch, have your network administrator disable spanning tree on that port. Otherwise your computer may duplicate the AppleTalk address of another computer on the same network and both network connections may become unreliable.
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