Q: Why is my iMac slow to recognize my ethernet connection

Is the Ethernet choice in the top of the selections available, as a priority,

above all others? If wi-fi is higher on the list, or if Ethernet is not active

such a situation may be a reason why that is slow to connect...

You may need to look into Network settings to see if this should be changed.

Also see what Console logs (if any) may suggest about this matter.

Even a re-start into Safe Mode, repair disk permissions, and a regular re-start

may help in some circumstances where the matter has little to do with Ethernet.

There likely are specific logs that may point to underlying causes.

But I'm not sure how to retrieve them or of another cures outside

the settings in Network and other devices that may be acting up

and should be disconnected when you are troubleshooting.

Good luck in this matter!

Hi frankfromduluth !

I've the same trouble with my imac 27 Fusion drive 2014 i5 3,5Ghz 8 Go ram  !!

it takes a minute to reconnect by lan !

Have you find a solution ?

Intel Core i5

I think I've find something

iMac slow to connect to internet over ethernet

Hope this help !

There may be some details among the linked information in this Support article:

•Solutions for connecting to the Internet, setting up a small network, and troubleshooting - Apple Support

Sometimes, depending on other circumstances, the issue may relate to this topic:

•Non-responsive DNS server or invalid DNS configuration can cause long delay before webpages load - Apple Support

In any event...

Good luck & happy computing!