Wifi just goes away!  



iMac with 10.13.6,  When I restart the system, wifi connects and works just fine.  For awhile.  But, how long is random, a day, a few days, a few hours, whatever.  Then, it just drops.  I have may other devices and my home wifi continues to work fine.  I use the Google mesh, connected to Xfinity router.

When it hangs, if I try to connect to any other wifi, it hangs, like wifi is no longer operational.  I tried stopping and restarting the wifi.  No luck.  So, I must reboot to regain a connection.

Does having two wifis in the house cause it to just drop all connections?  My macbooks and ipads do not have this issue.





Try booting into Safe mode
This will not load any 3rd party additions, it will load some more conservative Apple drivers (may cause screen flicker), and it will clear some kernel caches (a cache is saved data in a form that can speed up a program, but is totally redundant to the original source, and thus can be safely cleared).  Booting into Safe mode is just an experiment, but can frequently eliminate any 3rd party interference, or a cached item out-of-sync with the world.  (Verify Safe mode via Applications -> Utilities -> System Information -> Software -> Boot Mode -> Safe vs Normal)
I'm suspecting 3rd party interference.
Run with Safe mode as long as you can stand it (it is not the best, but it gives you conservative drivers and no 3rd party additions.
If you can run long enough to show that WiFi behaves normally (or your reboot experiment in the other post works), then you may want to run and post the EtreCheck output so we can see what 3rd party additions you have installed.
Click on the Share icon and select "Copy Report"
And then Paste the report as an "Answer" to this thread.
If, AND ONLY IF, you get the error when pasting or posting the report,
then try posting to, and give us a PasteBin URL link.
EtreCheck is a tool that helps debug problems without any access to the troubled computers. Debugging problems can be a difficult task even when the machine is in front of you. Attempting it via a forum post is extremely difficult. EtreCheck is a great help that regards.

Even though your other devices work fine, it may still be worthwhile to restart the router and access points.




I agree with what others have said on this thread but also wanted to add that I would make sure that your Google mesh WiFi system is setup in bridge mode as you will only want one router on your network. Having two different WiFi's should not be causing this problem but it does add to the complexity as it is way to easy to have your devices connect to the wrong WiFi and then not have access to some or all of your other local devices.

Having said that, I am with @datafornothinandbitsforfree that I do think it is some 3rd party software that is causing the problem and I would also run though the troubleshooting steps that he has outlined above as well.