2018 Macbook Pro loses internet connection but NOT wifi

Discussion in 'MacBook Pro' started by noughtme, May 1, 2019.

  1. noughtme macrumors newbie

    Joined:
    Jan 11, 2019
    #1
    Another hilarious problem with the 2018 Macbook Pro.

    This has started happening multiple times a day in the past couple weeks, at home and elsewhere. Full strength wifi connection, but no internet connection. Always takes me a moment to notice, because I'm just thinking the website is taking a while to load, then I notice the indicator in the Airport Utility is orange, so there's a network connection, but no internet.

    I've got other up to date Macs running the same OS version. No problems with them.

    This happening to anyone else?
     
  2. solouki, May 2, 2019
    Last edited: May 2, 2019

    solouki macrumors member

    solouki

    Joined:
    Jan 5, 2017
    #2
    Hi noughtme,

    I've been having this exact type of WiFi disconnection since the very beginning of my use of the 2018 MBP. It has continued through 3 different 2018 MBPs and all macOS High Sierra and Mojave updates. These problems stem from a loss of the DNS information by the 2018 MBPs, all while the WiFi hardware is still working. I have performed packet capture (Wireshark) while the 2018 MBPs were disconnected and found that the WiFi hardware was still sending and receiving packets. These WiFi disconnects cause all other types of problems, for instance, I have experienced Safari disconnects, Software Update (macOS 10.14.3 update) failures, Mac App Store update failures, Mac App Store installation failures (Xcode, Logic Pro X, in particular), TeXLive installation failures, SageMath install failures, Time Machine backup failures (4 times for initial TM backup, 5th time took 5 and 1/2 days to complete, probably because of WiFi disconnects), AirDrop failures, rsync failures, ssh failures, ping failures, and even SMB-mounted HDD deleted files, all caused by the WiFi disconnection problems.

    I have experienced these WiFi disconnections on four different WiFi routers also, so they are not restricted to just one router type. All of my other computers, including other macs, iPhones, iPads, HomePod, AppleTV, PCs running Linux, Raspberry Pis, B&W speakers, etc. still maintain Internet and intranet connectivity to the same router while the 2018 MBP is experiencing a WiFi disconnection. In other words, these WiFi disconnections are specific to the 2018 MBP.

    I also experience the occasional bluetooth disconnections.

    The following link to a post on this forum explains some of these issues:

    2018 MacBook Pros crashing with "Bridge OS" error

    Note: In my hands, these WiFi disconnections are rare (I see them 1 to 5 times a day), random (there is no pattern to when or why they occur), and often intermittent (they will often fix themselves, typically in under a minute and usually by 5 to 30 minutes, but I've also waited over 16 hours and not had a WiFi disconnect fix itself -- so they don't always fix themselves). You can manually fix these WiFi disconnections by switching off your WiFi and then turning it back on.

    Regards,
    Solouki

    P.S. I know you are being facetious when you use the adjective "hilarious", but because of these WiFi disconnects I have stopped using my 2018 MBP and returned to using my iMac and 2016 MBP for system critical work. I can't risk having a WiFi disconnect corrupt my SMB-mounted disks. Over the last decade I have owned over ten high spec CTO mac computers, and the 2018 MBP is the only one that I experience these problems, all of the others worked well.
     
  3. BrianBaughn macrumors 603

    BrianBaughn

    Joined:
    Feb 13, 2011
    Location:
    Baltimore, Maryland
    #3
    I have to conclude that you're running some sort of Apple router since you mentioned Airport Utility. If you had the other Macs sitting side by side with the 2018 and running Airport Utility would everything be "green" on those?
     
  4. solouki macrumors member

    solouki

    Joined:
    Jan 5, 2017
    #4
    To answer your query, in my hands, I've experienced WiFi disconnects to four different WiFi routers, three with a SNR of 45 to 50 dBm (RSSI=-40dBm, Noise=-90dBm) and one with a SNR=25dBm. Two of these routers were Apple Time Capsules using 802.11ac on the 5GHz bands (80 MHz bandwidths), one was an hitron 802.11ac router, one was an unknown router at my office. For the two Time Capsules, Airport Utility shows the 2018 MBP as being connected with all green lights, but the 2018 MBP has lost its DNS information. Thus the 2018 MBP, while its WiFi hardware is still operating, it cannot talk to machines on the Internet because it has forgotten its DNS information. And, since I run my own DNS server at home, my other computers/equipment also have local DNS names, and the 2018 MBP cannot talk to these machines either when it is experiencing its WiFi disconnects because it has forgotten the local DNS names too.

    I get "unknown host" errors when the WiFi disconnects ... even in the middle of a file transfer using rsync or ssh, I'll see 10000 files transfer okay and then a failure on the next file and after a 90 second timeout an "unknown host" error. So, the 2018 MBP has somehow forgotten its DNS information in the middle of executing an rsync or ssh command. I've also seen the same midstream "unknown host" errors while printing to a WiFi printer, while scanning from a WiFi scanner, and while AirDropping files both to and from other computers and an iPhone.

    Regards,
    Solouki
     
  5. coach_ditka macrumors newbie

    coach_ditka

    Joined:
    Mar 1, 2019
    Location:
    Illinois, USA
    #5
    Solouki, have you had the same experience using manually entered DNS vs. assigned by DHCP?
     
  6. chipchen macrumors 6502a

    Joined:
    Oct 30, 2002
    #6
    This happened to me once... and I did nearly everything: updated my software, re-installed the operating system, tried booted from different hard drive, hard reset the router, etc, etc.... Anyhow, long story short,... it wasn't until I updated the firmware (or re-installed firmware) on the router that fixed it. I still don't know what happened since it worked before a certain point, but re-installing the router firmware fixed it. Might be worth a shot.
     
  7. solouki, May 2, 2019
    Last edited: May 2, 2019

    solouki macrumors member

    solouki

    Joined:
    Jan 5, 2017
    #7
    Yes, I run my own local DNS server, and thus have entered the DNS names and the assigned IP addresses of most, but not all, of my local machines. These local names are supplied to any machine on my LAN, including mac computers, wifi speakers, iPads, iPhones, Apple watches, AppleTV, wifi routers, ethernet routers, laser printers, HP scanner, Raspberry Pis, PCs running Linux. All of these machines, except the 2018 MBPs when they are experiencing a WiFi disconnect, have access to each other on my LAN via DNS names. I have also tested a wifi router that excludes my local DNS server and thus only has access to specified local IP addresses or Internet DNS names through my ISP's DNS server or through one of Google's DNS servers. Once again, the 2018 MBPs experience WiFi disconnects to the Internet through this router too (while all of the other machines maintain WiFi Internet connection when using this router).

    Solouki
    --- Post Merged, May 2, 2019 ---
    Thanks, but I've done this also on three of the four routers that I've tested -- does not solve my rare, random, and often intermittent WiFi disconnect problems with the 2018 MBP. I appreciate the suggestion though.

    EDIT: Your problem appears to be different than my WiFi disconnects, however, since once my WiFi is cycled off and back on (say while reinstalling the operating system or booting from a different hard drive), the WiFi disconnection is fixed.

    Solouki
     
  8. noughtme thread starter macrumors newbie

    Joined:
    Jan 11, 2019
    #8
    The Airport Utility, while providing extra functions for Apple routers, will still indicate network or internet connection (or neither) with any router or access point. Usually, by the time I notice, it's too late to open terminal or perform any diagnostics because it resolves itself.

    At home, my 2010 Macbook Pro, Mac Mini, iPhone, Raspberry Pi's and various IoT light switches maintain internet connection while my 2018 Macbook Pro drops connection.

    At work or out my 2018 Macbook Pro drops internet connection while my iPhone never loses internet.

    Solouki: It is not actually very hilarious.
     
  9. BrianBaughn macrumors 603

    BrianBaughn

    Joined:
    Feb 13, 2011
    Location:
    Baltimore, Maryland
    #9
    Right. You've checked all of your settings at System Preferences>Network for anything strange as well as scanned for malware?
     
  10. noughtme thread starter macrumors newbie

    Joined:
    Jan 11, 2019
    #10
    Nothing unusual in Network Preferences. Haven't installed anything in the last two weeks (except the latest update!!!).

    I could start running something to generate a log if I can't ping the network, but that sounds like work.

    Between this and the T2/audio/speaker problem I also have, I'm just waiting for the keyboard to give out.
     
  11. solouki, May 2, 2019
    Last edited: May 2, 2019

    solouki macrumors member

    solouki

    Joined:
    Jan 5, 2017
    #11
    As I mentioned above, I knew you were being facetious with "hilarious" -- and for me it means that I cannot trust the 2018 MBP with system critical work; it is a gargantuan expense down the drain for me.

    And your WiFi problem sounds precisely the same as my WiFi problem. If you ever figure out a solution, please let me know.

    Yes, I have checked all network settings, as I'm fairly experienced with network administration. You have to understand that it is only the 2018 MBP that looses its WiFi connectivity (DNS information, to be specific), while all of my other computers and equipment stay Internet and intranet connected, including a 2016 MBP that has exactly the same network settings as the 2018 MBP. I scan for malware every night and I run a sentry that checks continuously for suspicious activity. In addition, I run a reverse firewall to make certain that nothing untoward is happening (a requirement for some of my consulting) on the machine. Also, these WiFi disconnects occur even when no other software is installed.

    For example, just today I received the 2018 MBP back from Apple Service for an unfixable corrupted internal SSD problem as well as the WiFi disconnect problem. Apple replaced the logic board as well as the touch ID board (is the T2 on this board?). When I turned on the 2018 MBP, fresh out of the repair box, and setup my account, the MBP immediately notified me that the 10.14.4 macOS update was available. So, before doing anything else, I attempted to download and install the update, but, believe it or not, the WiFi disconnected in the middle of the 10.14.4 download, killing the update. I cycled the WiFi off and then on, and then completed the 10.14.4 download and install. So, with no other software installed on the computer, it suffered a WiFi disconnect (I checked that "ping www.apple.com" failed with an unknown host error.) Basically, I have been unable to ascertain any pattern in the WiFi disconnects, thus I say that they are rare, random, and often intermittent.

    Solouki
     
  12. Alumm Pro macrumors newbie

    Alumm Pro

    Joined:
    May 20, 2019
    #12
    Are you using a USB-C adapter when your MacBook have WiFi issues?

    https://www.intel.com/content/www/u...al-bus/usb3-frequency-interference-paper.html

    Some adapters do cause WiFi interference (described in above Intel paper), cuz they are poorly shielded.

    Feel free to check out our USB-C adapters WiFi test.
     
  13. zarathu macrumors 6502

    zarathu

    Joined:
    May 14, 2003
    #13
    Maybe your mac is momentarily going to sleep because of a specific line of code that is screwed up. In my case its a kernal extension to do with ethernet and affects two mother boards in the 2013-2015 models. Not all of them have the problem. You can remove the code, or connect it to a high level connection. Or you can buy a little piece of software that causes it to do 25000 to 40000 idle wakeups for each cpu second.
     
  14. noughtme thread starter macrumors newbie

    Joined:
    Jan 11, 2019
    #14
    not using a usb-c adapter when the problem occurs, although i did notice this issue when i got my first USB 3.0 memory stick (doesn't seem to be an issue with quality brands).

    interesting theory about kernel extensions. the only kernel extension i seem to have is an RME audio driver. I can't see a USB audio driver causing an issue. I have more trust in the quality of RME drivers than I do apple, but I can check it out, although the appearance of problems does not coincide with the most recent driver update.
     

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13 May 1, 2019