I had this issue several times. Changing Settings > Network Setup > Ethernet Speed to Fixed 100mbps seems to have resolved the issue so far.
Just checked and It was set to that. I've got another update to run so I went through your steps and will try again. Thanks.
My solution was not the answer. My hub went off line again. I am using the community xiaomi driver and the xiaomi temperature sensor and xiaomi motion sensor were the last activities in the log before it went offline. I am going to remove those and see if that helps.
Is there a way to get more detailed error logs?
