Wifi/Internet problems with MBP - fixed by rebooting router/cable modem

January 22, 2021 7:16 AM

Frequent critical internet (zoom/browsing) failures with 2012 Macbook Pro on Mojave…… but other machines on network work fine. Temporarily fixed by rebooting router and cable modem, but always returns. WTF?

I have a 2012 MBP running Mojave, 16GB RAM, 1TB SSD. Every few days, my internet becomes slow/non-responsive - as in chrome won’t access any site for a few seconds to a full minute. Another more critical manifestation of the same problem is zoom just refuses to stream for minutes at a time killing my work - it makes zoom & other videoconferencing unusable! At the SAME time on exactly the same network, my spouse’s computer (a newer macbook pro) works fine, as does my phone, as does a PC. I’ve tested zoom on another machine with the same account within a minute, and it ain’t my zoom account or slowdowns on the zoom network. I am within 15 feet line-of-sight to the router; the wifi signal is fine, and the bandwidth is good, signal:noise is good (no significant interference from nearby wifi channels).

This can reliably be fixed by resetting BOTH the router AND the cable modem (not either), but the problem returns in minutes to days. The reboot takes ~5 minutes and I can’t use this as a solution as I need to conduct meetings and classes on zoom reliably!

Updated my computer and software to the latest versions of Mojave (10.14.6), Zoom (5.49), Chrome ( 87.0.4280.141). I have updated my Router (a NEW! TPLIink Archer AX3000) to latest firmware; it is connected to my TPlink cable modem (TC-7620). I can upload pages of configs if people want to see my Router config setup which is pretty standard.

Activity monitor on my Mac shows plenty of memory, plenty of CPU capability, plenty of bandwidth available. This happens when I’m just running zoom by itself and no other apps open!

I’ve tried to use a timeswitch to reboot the router and cable modem overnight, but this doesn’t stop the occurrence, only delays it.

It seems like “something” about the cable modem/router config ‘decays’ over time (or a buffer gets full or something ‘drifts’) and my older macbook can’t deal with this time-dependent problem, but newer devices can. Either that or my mac has an intermittent/time dependent fault or config that the router/cable modem combo can’t deal with….

What do you recommend I do to fix the problem or diagnose it?

Hope me mefi!

posted by lalochezia to Technology (18 answers total)

What's the DNS setting on the MBP? Does it match the setting on the computers that work?
posted by Thorzdad at 7:26 AM on January 22, 2021

DNS on mine is 192.168.0.1. Same on spouses MBP.
Also does zoom use DNS to access its services?
posted by lalochezia at 7:35 AM on January 22, 2021

Is it possible that parts of your setup are auto-migrating to IPv6? DNS gets weird when IPv6 is spotty.
posted by spacewrench at 7:40 AM on January 22, 2021

How many of these potential fixes have you already exercised?
posted by flabdablet at 7:42 AM on January 22, 2021

This is a bit squirrelly and a total guess, but I've seen issues with Macs and TP-Link routers if the WPA passphrase has spaces in it. Can't remember whether Mojave was specifically involved or not.
posted by flabdablet at 7:44 AM on January 22, 2021

IPv6 is disabled on the router. No spaces in passphrase. No new USB-c hardware nearby- I've had this problem in different parts of the apartment, so I don't think it's proximity to other sources of interference.

---

I will try the potential fix " Make a New Wi-Fi Configuration in MacOS Mojave", from that link, flabdablet!

---
I was going to do this from your link "Create a New Network Location with Custom Settings" and lower the MTU....

I tested my MTU at 1500 using the link below and currently it's fine, but of course, my wifi is working fine now

https://macgurupro.com/managing-mtu-size-mac-os-x/

100 packets transmitted, 100 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 12.116/39.543/652.823/77.957 ms

But I will try this as a next step if Make a new wifi config doesn't work.
--


Please keep suggestions coming! Given the intermittent nature of this problem, I don't believe it's a corrupted set of config files or my MTU, so I'm happy for more suggestions.
posted by lalochezia at 8:07 AM on January 22, 2021

Could it be that some other device had grabbed your Mac's local IP address from the router and your Mac has to negotiate with the router for a new IP address? This would manifest as your Mac getting fully dropped from the network for a little while, not as just a slowdown. I can't remember how to fix this but it has something to do with assigning each machine its own local IP.
posted by heatherlogan at 8:38 AM on January 22, 2021

Another thing that makes wifi get flaky after working for some while is power saving gone wrong. If your macbook has an option to turn the wifi off when idle to save power, and it's currently on, try turning it off.

DHCP not working right when an IP address lease expires could be another culprit. Should be able to eliminate that by using the router's DHCP settings to reserve a fixed IP address for your macbook's wifi MAC address.

Or you might be looking at hardware failure. You could try plugging in a little Edimax USB wifi adapter and see if it connects more reliably than what the macbook has built in.
posted by flabdablet at 8:50 AM on January 22, 2021

I am within 15 feet line-of-sight to the router

If you were me, you'd be using one of these. Because, honestly, fuck wifi.
posted by flabdablet at 8:57 AM on January 22, 2021

Line of sight=across my apartment through dining room and living room. But yes, plan-b (or c) is to buy a 50-ft ethernet cable, if the problem starts happening, desperately quickly string it across my apartment (like a laundry line in a busy tenement apartment) between router and computer, and if that fixes the problem in real time, just route the cable more neatly round the skirting boards of my apt like satan intended.
posted by lalochezia at 9:02 AM on January 22, 2021

route the cable more neatly round the skirting boards of my apt like satan intended

Are you aware of flat Ethernet cable? It works well and makes for some pretty tidy satanic routing.
posted by flabdablet at 9:14 AM on January 22, 2021

I had a vaguely similar issue with Catalina, where the network would get hung up, browsers would stop being able to do anything, programs wouldn't launch. I reinstalled and it went away, so I only have a post-hoc diagnosis, but it seems like the problem may have been ocspd getting hung up. It doesn't sound quite like your problem, but it's an easy enough thing to try the quick workaround that I'll pass it on: kill ocspd. It will restart itself after a few seconds, and be happier. If that works, I think there's more you can do about it to clear the problem away.

Example:
xxxx@xxxx-rmbp-13 ~ % ps -ef |grep -i ocsp
0 51318 1 0 7:54AM ?? 0:03.08 /usr/sbin/ocspd
501 53176 53119 0 11:15AM ttys000 0:00.01 grep -i ocsp
xxxx@xxxxx-rmbp-13 ~ % sudo kill 51318

(Explanation: ocspd is responsible for checking signing certificates. These are used for almost all web traffic, and they're used on your mac to verify the authenticity and integrity of the programs you're running. It does those checks over the internet if the internet is available, but it can get hung. Resetting everything would be enough to break out of that hang. In theory I think its worst faults have been fixed in the last two-three months, but I don't use Mojave anymore.)
posted by wotsac at 11:29 AM on January 22, 2021

I had similar problems with a flaky modem. After trying various technical fixes, I bought a cheap timer and set it to turn the modem and router off for 30 minutes at 3am every day. That solved the problem.
posted by monotreme at 11:35 AM on January 22, 2021

The fact that everything on your network is working properly except the macbook says to me that the problem is with the macbook, or the macbook's connection to the network, not with the network infrastructure.
posted by flabdablet at 12:17 PM on January 22, 2021

I've had that issue with a phone on occasion, and turning the phone WiFi off and on fixed it. Resetting the router would no doubt have had the same effect - both things break and remake the WiFi network connection. Does it sort itself out if you turn the Mac wireless off and on again?

And I suspect you're finding you have to reset both router and modem not because they both need resetting but because the router comes up without a wan address and the modem is disinclined to share it. I've seen that before, too.
posted by How much is that froggie in the window at 6:29 PM on January 22, 2021

This can reliably be fixed by resetting BOTH the router AND the cable modem (not either) - This doesn't make much sense, as far as the computers on your home network are concerned the cable modem doesn't exist, they only talk to the router.

I would guess that the time that it takes for both your cable modem and router to go away and come back is what triggers your Mac to do some re-initialization work that gets it back online.

flabdablet's "The fact that everything on your network is working properly except the macbook says to me that the problem is with the macbook, or the macbook's connection to the network, not with the network infrastructure." is almost entirely right but for maybe all the other devices on the network are Macs running pretty much exactly the same version/configuration and just your Mac doesn't work while the rest work just fine. There's still room for you being the only Mac on the network and your WiFi router not playing nice with Mac products. I've had to deal with much weirder things just like that. (heh, I managed a RegEdit patch from Microsoft for not playing according to the rules of the RFCs over broadcast behavior and DHCP wonkyness).
posted by zengargoyle at 11:42 PM on January 22, 2021

maybe all the other devices on the network are Macs running pretty much exactly the same version/configuration and just your Mac doesn't work while the rest work just fine

If that were the case, the first thing I'd be checking is whether the problem still exists when the macbook is connected to the network with a nice reliable chunk of wire instead of a wibbly wobbly radio signal with ten squillion obscure failure modes.

If trouble persisted, I'd then be looking closely into the OS's network configuration. If it didn't, I'd be trying a second wifi adapter.
posted by flabdablet at 1:11 AM on January 23, 2021

There are lots of discussions of this issue online. One answer pointed to this apple support document. The WiFi Diagnostic Tool referenced can be launched by holding down the option key and clicking on the WiFi icon in the menu bar.

There was a firmware update for the WiFi on 2012 MacBook Pro machines. Have you applied that?

Good luck
posted by blob at 2:55 PM on January 23, 2021