Self-assigned IP on Apple desktops while using ethernet

[Nomoremonopoly]

Intermittently my Apple desktop's will change from their IP address from DHCP  and assign themselves an IP address which does not work. This only affects the Ethernet connection, the wifi connection remains connected to the internet, but since working from home I am required by my company to remain connected through ethernet for the most reliable connection as I do call centre work and our software drops more calls over wifi. It happens on both my iMac desktop and my new MacPro but not necessarily at the same time. I have attempted to restart the gateway, reset my computers (i've partnered with Apple many times on a fix already), I have tried renewing DHCP lease, and I have switched out all my cables, purchased and tried a new ethernet switch and used the port directly from the gateway into the iMac directly with a KG ethernet cable, finally I have reset the firewall settings and it still receive the self assigned IP address. The Self assigned IP address will persist for hours before just switching back to a valid IP address where it will be fine for a few hours before happening again.

I have reached out to Shaw Support and the best I have gotten on this particular issue is everything looks fine on their end and that it is not within their scope of support. Im at a loss of what do to or what to try next. Any one here have additional insight?

[mdk]

@Nomoremonopoly -- after getting the self-assigned IP-address, use the IPCONFIG (on Windows, maybe IFCONFIG under MacOS) with the "/all" option, to show the IP-address assigned to your computer, and the IP-address of the DHCP-server that gave you that IP-address.

Since it happens to more than one computer, it's not likely to be a "bad" Ethernet adapter inside both computers. Not impossible, though.

What does MacOS do, when it finds more than one network adapter (wired & wireless)? Does it "load-balance" over the two connections, or does it route 100% of the network traffic over the "faster" connection, and lets the other connection go "dormant" (until its DHCP-lease expires?).

What happens when you disable the WiFi capability of your router, or disable the WiFi adapter on your computer, leaving the Ethernet connection as the only working connection for your computer?  Still get symptoms?

[Nomoremonopoly]

I had to teach myself how to use terminal but I think I get the hang of it now. the ip address I get from terminal is the same as the incorrectly assign Ip address in my network settings. This ip address is waaay outside my DHCP address range.

I cannot have both wifi and ethernet active at the same time because they will switch back and forth as the primary connection and it disconnects me from my air play devices and slows my connection considerably. if I do run them at the same and the ethernet goes self assign it the connection faulty dips to almost unusable until I disable the ethernet connection. if I disable the wifi on either my desktops or my router is does not seem to change anything for the ethernet connection and the symptoms remain.

[mdk]

@Nomoremonopoly  -- the ip address I get from terminal is the same as the incorrectly assign Ip address in my network settings. This ip address is waaay outside my DHCP address range.

OK. What IP-address do you see?

Something starting with "169.254" ?

If you have an older cable-modem, such as the HITRON, its DHCP-server should hand-out IP-addresses like "192.168.0.xxx".

If you have the BlueCurve cable-modem, its DHCP-server should hand-out IP-addresses like "10.0.xxx.yyy".

> I cannot have both wifi and ethernet active at the same time because they will switch back and forth as the primary connection

OK. That is to be expected. Both MacOS and Windows 10 seem to pick the "better" connection, and exclusively use that one connection, and ignore the other connection. Are you saying that your device is repeatedly switching between the two adapters? This would imply that one connection has unexpectedly gone "down", and MacOS is switching to the alternate network-connection.

> it disconnects me from my air play devices

Huh? If your cable-modem's WiFi access-point is going "down", and cutting-off access to all your WiFi-enabled devices, that is your problem; your MacOS device is not the problem.

> slows my connection considerably

What speeds are you observing?

What Internet speed are you paying to receive? "Fibre+ 300" ? 750 Megabits/second? 1000 Mbps? The Ethernet adapter in your MacOS device should receive at one of these speeds, and should send at 100 Mbps. Your computer's wireless network adapter might use the "Wireless N" protocol, receiving at up to 150 Mbps, or 300 Mbps if it uses two channels. Or, if the adapter uses the newer "Wireless AC" adapter, it should receive at the speed you are paying for -- 300 or 750 or 1000 -- and should send to the Internet at 100 Mbps.

> if I do run them at the same

Your computer won't let you -- it picks the "better" one, and ignores the other one.

> the ethernet goes self assign, it the connection faulty dips to almost unusable until I disable the ethernet connection.

Huh? If your Ethernet adapter goes to "self assign", it should completely stop communicating, not just "spiral-down". Then, the WiFi network adapter should "wake", and receive at the maximum speed for either the "Wireless N" or the "Wireless AC" protocol.

> if I disable the wifi on either my desktops or my router is does not seem to change anything for the ethernet connection and the symptoms remain.

That makes sense.

Without any WiFi connection to your computer, your computer will exclusively use the Ethernet connection. However, in your case, there is something wrong, in this configuration, if your Ethernet connection "dips". 

Leave your router and your computer in this configuration -- pure Ethernet & no WiFi -- and contact Shaw ( www.shaw.ca/chat ) or 1-888-472-2222, to get a Shaw Agent to determine why this "Ethernet-only" configuration is not "stable", and is not always receiving at your contracted speed, and is not always sending at 100 Mbps (through your BlueCurve).

[Thupthigwenwong]

Its shaw’s way of controlling user settings so they can throttle down your internet speeds.they are liars when they tell you anything else I recommend getting a reliable vpn.i am looking into this also.they are sneaky #%#%€£¥*+#%.while testing your speeds they will appear normal but behind the scenes shaw is taking your ip and most visited sites streaming activities p2p and willfully turning down the bandwidth you rely on and are paying for.there is an interesting artice on cbc with the crtc or ccrtc (officials responsible for the fairplay of the isp’s and consumers)NOT SURE THE ABBREVIATIONS ,in a meeting with the ceo’s of shaw and shaw refused to reveal the truth to the authorities also cbc.this all surrounds the issue of how they have taken away the consumers right of making an educated decision on what provider is most fair  with policies on throttling net speeds.isp’s are liars and theives stealing the customers money and putting the bandwith to their private partners and own interest at our expense.check out the lies in the cbc article its out there we need a consumer revolution #%£¥€!# all these companies inflation is a lie its greedy companies standing on our necks and rooting your pockets and bank accounts.