2018 MacBook Pro randomly losing WiFi connection

Finally found out what is causing issue and also fact that Macbook 2010 with Yosemite can react correctly.

Router cleans it's DHCP table (not standard behaviour and possibly bug) and asks clients with ARP if they are still alive. All devices (iPhone, iPad, Macbook Pro 2010) react. However for some reason Macbook Pro 2015 doesn't see any broadcast ARP request (wireshark screenshot from 2010 that there is traffic). This explains why router allows connections (cause there is no DHCP timeout on lease) but it doesn't allow outgoing WAN connection because it misses the ARP reply. Also tried ping from Macbook 2010 and the underlying ARP broadcast request can't be seen by Macbook 2015. Also no need to clean arp table on 2015. By triggering "arping 192.168.0.1" all connections will resume.

https://imgur.com/a/tQFDDXz

Some people solved this issue by changing router (other routers don't clean/check entries in DHCP table)

Here is a diff of sysctl (link layer) between Macbook 2010 and 2015:

net.link.ether.inet.arp_llreach_base: 120

net.link.ether.inet.arp_llreach_base: 30

net.link.ether.inet.arp_unicast_lim: 3

net.link.ether.inet.arp_unicast_lim: 5

net.link.ether.inet.maxhold: 16

net.link.ether.inet.probe_intvl: 7

net.link.generic.system.dlil_input_threads: 4

net.link.generic.system.dlil_input_threads: 6

net.link.generic.system.ifcount: 12

net.link.generic.system.ifcount: 7

net.link.generic.system.start_delay_disabled: 0

net.link.generic.system.start_delayed: 0

net.link.generic.system.tx_chain_len_count: 0

Tried "sudo sysctl -w net.link.ether.inet.arp_unicast_lim=0" from other thread without success ;(

Verified /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -I

Anyone can explain why Macbook Pro 2015 doesn't see ARP broadcast? Or which layer can cause this issue?

I have two different SSID's set up for 2,4 and 5GHz. In the past the MacBook reconnected to the 2,4GHz after connection loss of the 5GHz. But because of the fact that my Magic Trackpad (first gen) get's useless I set the 2,4GHz to ignore.

I had some speed degration, too but most of the time the connection get's lost completely. For now turning of awdl0 seems to be a useful workaround to minimise connection lost. But I'm still monitoring.

Just another data point. After a month of no problem at all, I started having wifi connection problems on my iPhone, 2019 Macbook Pro, and even my Simplisafe camera. I tried resetting all the devices, changing my wifi password, and a few other resets. But just disabling my Macbook's "unlock with Apple Watch" fixed it all at once. One additional datapoint--my 2018 iMac still unlocks with my watch with no problem.

I just had the issue again and ran this at a bash prompt:

networksetup -getairportnetwork en0

This gave me the result "You are not associated with an AirPort network."

Then I reconnected using this command:

networksetup -setairportnetwork en0 MyWifiNetwork

where MyWifiNetwork is my wifi ID. Then I was back in business. Running the first command again gave me:

Current Wi-Fi Network: MyWifiNetwork

So now I'll write a little script that uses the above commands to automatically check every few seconds and reconnect automatically.

Same thing on 2017 13" MBP (no Touch Bar). Will reset NVRAM/PRAM and SMC. If issue persist will be requesting RMA.

Have the tried the solution that was reported?

Turn off unlock with Apple Watch?

That is what has worked for me.

I have the same issue with my newly purchased 2018 macbook pro. Running macOS 20.14. Problem is only persistent when connected to an external monitor at work. Reboot fixes the issue for some time, then returns. Problem can be avoided by not closing the lid on the MacBook and use both the MacBook screen and the external monitor at the same time.

Thanks for the hint! I disabled awdl0 on my MBPro2018... let's see if it helps.

At least it sounds very plausible, because of several Apple devices with possible influences to the MBPro's WiFi at home. Starting with the iPhone7+, Apple TV3, and two iPads (one with iOS9, the other with iOS12) and an iMac 2011 with High Sierra.

The best for you to know when outage occurs is to have ping command with timestamp

ping 1.1.1.1 | perl -nle 'print scalar(localtime), " ", $_'

When you see outage try to ping default gateway. Tell us results (Can't ping default gateway, Can ping default gateway)

Keep running the continuous ping to the default gateway or to google.com or better yet do it to both from two different terminal windows. When you lose the connectivity, switch to the terminal windows and observe the ping responses. In my case, I saw occasional ping responses coming back even though most were lost.

Please report back back here if the connectivity loss is complete or partial based on the ping responses.

Interestimgly enough, back

in late January 2018 (when I bought this 2018 MacBook Air) and in early 2019, I experienced random disconnects from Wi-Finwith the Wi-Fi icon going gray. The MacBook Air wouldn’t automatically connect to the same or another known SSID until I would manually select the same (or another) SSID.

Some time in mid January this behavior changed with the Wi-Fi icon showing that the MacBook Air is still connected to Wi-Fi but IP connecttbeing lost.

I don’t know if a macOS update changed that behavior or if it was a firmware update for my Acess Point. The net result was the same, though, as network connectivity gets lost and can only be restored by manually disconnecting from Wi-Fi and manually re-associating to an SSID.

Personally, after I turned off the AWDL adapter with the WiFried utility, I didn’t see any change in my environment, as the access rate still degrade, and I haven’t had a loss of connectivity for over a week now since I replaced the UAP-IW-HD with the UAP-AC-HD and created a 5 GHz only SSID.

If it adds to the discussion... 2018 MBP 2.2 here. Wifi is fine with a dying Time Capsule. Horrible problems with this issue on two different Synology RT2600ac's with different firmware. I've been running a Ubiquiti USG + Nano HD AP for about 2 weeks now. It's working great across my home and the 2018 MBP hasn't had any issues. Maintains solid 1053-1300Mbps connections on 5Ghz AC from my normal workspaces. I've not experienced any weird disconnects or speed drops.

Same here. I use the first Apple Watch to unlock. Do you have a concrete suspicion that the Apple Watch is causing those Wi-Fi Problems?

In fact the unlock feature works with airdrop. Because if I disable awdl0 the unlock didn't work. Well, I'll give a try. I reactivated awdl0 and disabled the unlock with the Apple Watch. We'll see....

@cgn1026:

All I was trying to say is this:

If you experience another issue with Wi-Fi while auto-unlock with Apple Watch is disabled, then keep it disabled but also try to disable the Also Allow Nearby to Airplay option under Settings > AirPlay > Allow Access in your Apple TV4. Then, give it another try and let us know.

I went through several months of trying to solve the same problem. I tried an old AirPort Extreme router, which worked fine but was too slow. A friend gave me a router, which I plugged into my Comcast router. As long as I use the new router there are no problems. Apple tried everything, but nothing worked except for changing the router.

Did you try changing the Channel on your router?