Change advanced hardware options on Mac
In most cases, your hardware settings are configured automatically. In some network environments, you may need to set hardware options manually. Your network administrator or ISP should be able to tell you whether you need to adjust these settings, and, if needed, provide the specific settings.
Note: Changing your network settings affects the way your computer interacts with your network. Unless your network administrator has given you specific settings, use the automatic settings. Entering the wrong settings can affect network performance.
On your Mac, choose Apple menu > System Preferences, then click Network.
In the list on the left, select your network service.
Click Advanced, click Hardware, click the Configure pop-up menu, then choose Manually.
Use the pop-up menus to enter the settings provided by your network administrator or ISP.
If your computer and the device you’re connecting to support Gigabit Ethernet but the Ethernet cable you are using does not, you may need to adjust the Ethernet speed. Alternatively, you can purchase a cable that supports Gigabit Ethernet.