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> The dock apparently holds the mac address of the MacBook and retains the IP even when the MacBook isn’t docked. Thus when the MacBook is removed from the dock and connects to the Network via Wifi with the same Mac address it causes a conflict and worse, it locks the whole network.
We had Dell laptops with the dock. If you undocked the laptop under the right circumstances, which we could never determine, the dock would go into a mode where it would start spamming IEEE 802.3x PAUSE frames into the network as fast as it possibly could. Our switches didn't handle this correctly and would forward the PAUSE frame as it if it were a broadcast. When this happened, the entire network would cease to fun…
The switches one is a bear to debug. I just tossed out two old switches, because I wasn't sure which one was the one that polluted the network. I could have spent several hours, setting up little sandboxes, but it was easier just to toss them both, and get new ones.
I find it curious that the wifi interface and the USB/ethernet interface are using the same MAC address. Nothing keeps a computer from being attached with both at the same time, in which case this would definitely break things.
Also, doesn't Apple do MAC randomization on WiFi by default? So, it should be using the same MAC that already exists on the machine already.
It's one of the reasons given for why people say Macs "feel better" e.g. you sit down in a room with a friend who has a Dell. Your Mac gets WiFi almost immediately while they have to wait a few seconds even though both of you have been on this network before.
One of the benefits of owning the stack all the way from bare metal to OS to applications.
I used to have a dell vostro notebook that every time I logged into the network with windows, it would drop every other device on the wifi. Funny thing, is that if I used linux, the router would be alright and not collapse. Never found out the reason. In the end I divorced the wife and she got that notebook. Wifi is weird.
That seems like a pretty extreme solution to that problem.
We had Dell laptops with the dock. If you undocked the laptop under the right circumstances, which we could never determine, the dock would go into a mode where it would start spamming IEEE 802.3x PAUSE frames into the network as fast as it possibly could. Our switches didn't handle this correctly and would forward the PAUSE frame as it if it were a broadcast. When this happened, the entire network would cease to fun…
MAC addresses belong to the NIC and not the machine, and while the OS can override them, it won't do so without express user intervention. I'm especially skeptical of the Ethernet MAC being a duplicate of the Wi-Fi MAC, as this would cause obvious issues (especially considering both Wi-Fi stays up even in the presence of Ethernet, it's just that the routing table is configured to prefer the Ethernet over it) - if this was indeed the case, he would never have had network access on that machine.
However, it is known that some Realtek USB Ethernet controllers have unexpected behavior when powered but no longer enumerated on the USB bus, and they send some low-level Ethernet frame that effectively causes all traffic to stop on that L2 network segment. I'm not sure who is at fault (whether the controller or the switch it's connected to mistakenly rebroadcasting that frame), but here are more details: http://jeffq.com/blog/the-ethernet-pause-frame/ and https://lucumr.pocoo.org/2020/7/6/usb-c-network-hubs/.
My experience: 95% of all network problems are dodgy cables. The other 5% is dodgy switches. The switches one is a bear to debug. I just tossed out two old switches, because I wasn't sure which one was the one that polluted the network. I could have spent several hours, setting up little sandboxes, but it was easier just to toss them both, and get new ones.
My experience: 95% of all network problems are dodgy cables. The other 5% is dodgy switches. The switches one is a bear to debug. I just tossed out two old switches, because I wasn't sure which one was the one that polluted the network. I could have spent several hours, setting up little sandboxes, but it was easier just to toss them both, and get new ones.
And the final 90% is usually DNS's fault.
Earlier quoted context omitted.
Also, doesn't Apple do MAC randomization on WiFi by default? So, it should be using the same MAC that already exists on the machine already.
I believe Macintoshes "remember" the most recent IP they were given on a network rather than always doing a DHCP. It's one of the reasons given for why people say Macs "feel better" e.g. you sit down in a room with a friend who has a Dell. Your Mac gets WiFi almost immediately while they have to wait a few seconds even though both of you have been on this network before. One of the benefits of owning the stack all th…
Fuck everyone else my WiFi feels good.