Ethernet Drops Under Heavy Load - Randomly

[ImaginaryNerve]

So I've had the Mac Studio for a bit now and I love this machine. A few months ago, we upgraded our internet to 5 Gig fiber and it has been pretty freaking amazing, honestly, but about a week or two ago I started noticing that I would randomly lose my internet connection every now and then. It has been so intermittent that I'd been having a hard time pinning down exactly what's going on.

I'm connected via ethernet directly to AT&T's fiber device and most of the time I get full speeds or almost full speeds, usually within a few percentages of normal connection speeds and no drop during the speed test. Because of how random the dropping has been, a lot of it I assumed was due to server congestion, issues with HTTPS or some such noise, or even my VPN software.

I've removed any and all proxies and VPN software, but today I kept trying to download a video file and as soon as Safari's downloader reached just above 22 MB/s, my connection would drop. Since it happened several times in a row, I was able to do some troubleshooting through it and found that, with the Network pain of System Preferences pulled up, it shows the Ethernet disconnecting, then a self-assigned IP, then my normal IP address and access is restored.

I'm thinking it might be the ethernet cable, though it is brand new or it might be the port on the, err, fiber thing itself. I've a few ideas on how to test those but I'm also wondering if anyone may have any ideas on other troubleshooting steps I could try to rule out anything else.

I do have access to another Mac Studio, now that I think about it, maybe I should plug the ethernet in there and see if it does the same thing to rule out the ethernet port itself?

Networking isn't my forte, so I'm more or less just going by how I'd test other things.

 

[ImaginaryNerve]

Replaced the Ethernet cable and was able to download the file, so far so good. I'm really hoping that was the entire issue. I'd delete this if I could, I might've just jumped the gun a bit.

 

[Juicy Box]

What type of cable is it?

 

[Juicy Box]

Also, have you tried using another device to make sure it isn't your internet connection or overall network rather than just a Mac related issue?

I'm really hoping that was the entire issue. I'd delete this if I could, I might've just jumped the gun a bit.

There are some threads discussing some possible SW or maybe HW issues with recent Macs with the 10Gb Ethernet port.

One of the issues is when using CAT5e on a 1Gbps network. This should work perfectly fine, as CAT5e is rated as such. CAT5e, while not rated for it, can actually do 10Gbps over short runs.

Apple support has been directing people with this issue to switch to CAT6a or higher. This shouldn't be necessary, but they don't have an actual fix for this problem, yet.

With your situation (using 5Gbps link speed), you should be using a higher rated Ethernet cable that CAT5e, but if you were using CAT5e, that is most likely the cause of your issues.

 

[ImaginaryNerve]

Also, have you tried using another device to make sure it isn't your internet connection or overall network rather than just a Mac related issue?

The Mac Studio is the only one experiencing dropouts on Ethernet, I've also a PC and another Mac Studio on ethernet (though that one wasn't connected to the only 10Gb port on the device) but the only dropouts seemed to happen on the Mac Studio, which is why I assumed it was some odd issue with proxies, DNSes, and the like. New device, new ethernet cable, you wouldn't immediately assume hardware, you know?

With your situation (using 5Gbps link speed), you should be using a higher rated Ethernet cable that CAT5e, but if you were using CAT5e, that is most likely the cause of your issues.

I'm using Cat 6 cables, bought a few of them on bulk a couple months ago when we moved into this place. I'm a bit miffed that the one might already have gone bad, if I'm honest, so if things stay stable with the replacement cable, I'll probably purchase a higher quality one in a few weeks and slowly phase out the bulk order cables.

Thank you though, I appreciate it. The only thread I initially was able to find was discussing a USB Ethernet port with a similar issue though they weren't getting reconnected, they had to manually do it (iirc), whereas mine was just randomly disconnecting and then immediately reconnecting. So far though, we're sitting good and I've been stressing the connection as much as I'm able. There aren't too many sites out there that let you take advantage of these speeds, but I've already noticed I haven't been having some of the minor issues with certain apps that rely entirely on the internet, like before.

Going to keep stressing the connection for a few hours/few more days and see. Fingers crossed!

 

[ImaginaryNerve]

So I replaced the cable and it worked for a bit but this morning I got disconnected again, so I...said screw it and replaced it with a 10ft Cat 8 cable. Let's see how this holds up.

If it still disconnects, I'm gonna plug the other Studio in and see if it has problems. If it does, then I'll contact AT&T to replace the...modem? I'm not sure its technically a modem?...if it doesn't, then I'll contact Apple and send the Studio in for repair.

 

[Fishrrman]

OP:

I seen a suggestion posted in other threads about flaky internet/ethernet.
I didn't archive the posts, so I'm "recollecting from memory" here.

Try this:

For ethernet, you need to go to the network preference pane (or is it now the "settings" pane?)

I'm using Mojave as I write this, and I know "the look" of the pane has changed somewhat, but the essentials should still be there.

You need to click ONE time on the "ethernet" item in the list on the left.

Then, if there's an "advanced" button, click that.

Now you should see a pane with a bunch of "sub-panes" available.
One of them should be "hardware".
Click that.

Now, you should see several popup selectors.

I believe the topmost should be "configure", and the default setting for that will be "automatic".

Click on that and pick "manually".

Now, you have access to the other selectable parameters.

I suggest you go to "MTU" -- the default setting should be "standard (1500)".
Change it to SOMETHING ELSE for a moment.
Then, CHANGE IT BACK to "standard (1500)".

At this point you've really "changed nothing" (insofar as the settings are concerned" -- all you did was make some manual adjustments instead of leaving it at "automatic".

Leave the first popup at "manually".
Now, close the Network pane and reboot.

Even though no parameter was actually "changed", the fact that the user "went into" the network/ethernet/hardware pane and "adjusted" some settings may make a difference.

See if this changes anything over the next day or two, and let us know...

 

[ImaginaryNerve]

Sometime tomorrow or the next day, AT&T's going to send me a new gateway. Using any of the other ports don't seem to cause any dropouts and the switch connected to the 5 Gb port is getting random dropouts. It took a couple days, but I was able to (hopefully) narrow it down to the AT&T Gateway. If the new one has problems, I'll try the MTU "change" and then call Apple for a replacement.

 

[purplefuku]

OP:

I seen a suggestion posted in other threads about flaky internet/ethernet.
I didn't archive the posts, so I'm "recollecting from memory" here.

You have to wonder if this is the same issue that some of us are having with our M2 Pro Mac minis! Actually, I've even had these dropouts start happening on my Mac Studio & my old 2012 Mac minis! Changing from auto to manual seems to have fixed it on every device I've had issues on, so maybe this is just a long standing bug? I'm leaning more towards a bad network switch or a combination of software & certain networking hardware, though...

 

[southerndoc]

System Settings -> Network -> Ethernet -> Details -> Hardware

Set to manually, speed for whatever you're using (1G/2.5G/5G/10G), duplex to either full-duplex or full-duplex/flow-control, and MTU to 1500/standard. AVB/EAV mode should be disabled.

If you have energy efficient ethernet enabled manually or if it's automatically doing it, that may be causing your dropouts.

 

[Friend Trend]

I'm having the same issues with my Mac Studio. Running Cat6E on a 1G. Drops out 2 or 3 times a day for about a few second (enough to disrupt a zoom call for about 10 seconds - which always hits at the worst possible time!). No other devices on the network have this problem. I plan to try a USB->Ethernet dongle to see if that fixes it.

 

[MacDaddyPanda]

Have you tried using different DNS settings? 1.1.1.1 or GOogles. 8.8.8.8?

 

[Friend Trend]

Have you tried using different DNS settings? 1.1.1.1 or GOogles. 8.8.8.8?

I haven’t, but I’ve run ping tests and I’m not even able to ping other machines on my network. So I doubt it’s a DNS issue.

 

[ImaginaryNerve]

I'm having the same issues with my Mac Studio. Running Cat6E on a 1G. Drops out 2 or 3 times a day for about a few second (enough to disrupt a zoom call for about 10 seconds - which always hits at the worst possible time!). No other devices on the network have this problem. I plan to try a USB->Ethernet dongle to see if that fixes it.

Replacing the Gateway seemed to have fixed the issue for a couple days but then it started cropping back up again. I went ahead and removed some of the energy saver settings--my Studio no longer goes to sleep, no matter how long it sits and doesn't even turn off my monitor--and that seems to have fixed it. Haven't had the issue pop up yet. I started a chat with Apple about it but had to switch to a phone call the next day.

I think what's happening is it is randomly going into a low-power or sleep mode because the issue is most notable after waking it up from sleep and happens a few times afterwards.

I've also been having problems waking the Studio from sleep--sometimes it'll act like it restarted, reopening all the windows and Firefox/Safari will reopen but not on the websites they were on previously, I can't access the Studio remotely even though "wake for network access" is selected, etc. This makes me think it might be some kind of software issue.

I'm calling Apple about it on Monday, though.

 

[southerndoc]

Replacing the Gateway seemed to have fixed the issue for a couple days but then it started cropping back up again. I went ahead and removed some of the energy saver settings--my Studio no longer goes to sleep, no matter how long it sits and doesn't even turn off my monitor--and that seems to have fixed it. Haven't had the issue pop up yet. I started a chat with Apple about it but had to switch to a phone call the next day.

I think what's happening is it is randomly going into a low-power or sleep mode because the issue is most notable after waking it up from sleep and happens a few times afterwards.

I've also been having problems waking the Studio from sleep--sometimes it'll act like it restarted, reopening all the windows and Firefox/Safari will reopen but not on the websites they were on previously, I can't access the Studio remotely even though "wake for network access" is selected, etc. This makes me think it might be some kind of software issue.

I'm calling Apple about it on Monday, though.

If you leave the ethernet adapter settings to auto, then it can go to sleep. See my fix above. It fixed the issue on my own Mac Studio as well as my neighbor's.

 

[ImaginaryNerve]

If you leave the ethernet adapter settings to auto, then it can go to sleep. See my fix above. It fixed the issue on my own Mac Studio as well as my neighbor's.

I apologize, I should've mentioned I've attempted that as well when you posted it. It is still set to "manually". I was half asleep when I commented prior. I need to make sure I'm more awake before I reply!

 

[Friend Trend]

A follow-up from a previous post. After getting frustrated with having multiple drop-outs per day, I bought a $20 USB-C to Gigabit Ethernet dongle and connected to my network through that instead of the Mac Studio's built-in port. I haven't had any dropouts since. Frustrating that this is required - there's obviously SOMETHING wrong with how that port is configured - but I'm happy to have a solution.

 

[Fishrrman]

Friend Trend -

WHICH Ethernet dongle did you get?
Were any drivers or other considerations involved?

 

[MacGizmo]

I recently updated my eero Pro router to one of the new eero 6 Plus routers (to go with the gigabit service I have at the house) and immediately experienced timeouts that would not really affect local network connectivity, web surfing or emailing, but absolutely wreaked havoc with our company VPN software. It would disconnect me 3 or 4 times per hour. From what I've read, VPN's are very picky with the connections and the slightest dropout can disconnect you.

I tried different ethernet cables (cat 6, and an old cat 5 I had laying around) and nothing seemed to help. Switching back to the older eero Pro router fixed the problem immediately.

Oddly enough, I get the same download/upload speeds using the older router as I did with the newer one that was supposedly "optimized" for gigabit speeds. Maybe it was the WiFi 6 part of the router that wet the bed.

So in my case, it's not the Mac Studio or the ethernet cables that were the problem.

 

[handheldgames]

Restarting seems to reduce the issue.

 

[ascender]

Weirdly enough this has started happening to my M2 Ultra in the last week or so. I already had my speed and duplex settings on manual, so I'll try more regular reboots to see if that makes any difference.

 

[StoneJack]

Weirdly enough this has started happening to my M2 Ultra in the last week or so. I already had my speed and duplex settings on manual, so I'll try more regular reboots to see if that makes any difference.

similar solution. USbc dongle.