I connect my Mac to the ethernet using an adapter, and it shows Connected in network settings. However, if I let my Mac go to sleep without unplugging the adapter and then wake it up later, it displays a 'self-assigned IP' in the network settings
However , If I unplug and replug the adapter, it connects back.
How to overcome above?
MacBook
First, follow the first three steps in the Apple Support article Connect your Mac to the internet using Ethernet to reach your ethernet network settings. (You may see "advanced" or "details" for your ethernet service.)
You will see a self-assigned IP address ("link local" address). For example 169.254.x.y
Click TCP/IP in the sidebar, and click the button "renew DHCP lease".
You may be asked to apply network settings, but once the renew request has gone to your router, your ethernet adapter should receive a valid IP address and your connection be restored.
If this is a regular problem for your adapter waking from sleep, and your adapter is connected directly to your MacBook (not via a hub which must also wake up) then it's possible that your particular adapter wakes from sleep but does not send (or does not receive) the DHCP request for an IP address.
One possible solution could be to assign your ethernet adaptor a fixed IP address [using the remainder of the Apple Support article] instead of the default "using DHCP" setting.
The manual address you choose should be outside the range of IP addresses distributed by your router. Or your router may allow you to pre-assign IP addresses so that your adaptor is always granted the same address each time.
You may also be able to log on to your router to see whether it believes it has allocated (and sent via DHCP) an IP address for your adaptor to use, but your adapter has not received it correctly and therefore is using a temporary self-assigned address until it does receiv.
I am not certain this is the issue you have. Of course, it's good to check for any software updates your adapter might need.
First, follow the first three steps in the Apple Support article Connect your Mac to the internet using Ethernet to reach your ethernet network settings. (You may see "advanced" or "details" for your ethernet service.)
You will see a self-assigned IP address ("link local" address). For example 169.254.x.y
Click TCP/IP in the sidebar, and click the button "renew DHCP lease".
You may be asked to apply network settings, but once the renew request has gone to your router, your ethernet adapter should receive a valid IP address and your connection be restored.
If this is a regular problem for your adapter waking from sleep, and your adapter is connected directly to your MacBook (not via a hub which must also wake up) then it's possible that your particular adapter wakes from sleep but does not send (or does not receive) the DHCP request for an IP address.
One possible solution could be to assign your ethernet adaptor a fixed IP address [using the remainder of the Apple Support article] instead of the default "using DHCP" setting.
The manual address you choose should be outside the range of IP addresses distributed by your router. Or your router may allow you to pre-assign IP addresses so that your adaptor is always granted the same address each time.
You may also be able to log on to your router to see whether it believes it has allocated (and sent via DHCP) an IP address for your adaptor to use, but your adapter has not received it correctly and therefore is using a temporary self-assigned address until it does receiv.
I am not certain this is the issue you have. Of course, it's good to check for any software updates your adapter might need.
Self assigned IP after awakening mac from sleep
