Anders Brownworth

Technology and Disruption

MacBook Pro Ethernet Problems

There seems to be an Ethernet issue with Apple?s latest Intel based laptop, the MacBook Pro. My machine experiences terrible packet loss when connected to some Ethernet LANs seemingly without any rhyme or reason. I would typically see about 60% to 70% packet loss when pinging another host on the local network. Plugging my older PowerBook into the same network and pinging that same host resulted in 0% packet loss and plugging the two Macs directly into eachother without a hub or a switch in the middle worked perfectly as well. So I tried an assortment of hubs and switches guessing that there was a problem on the electronic signaling layer. Still no luck! So I called Apple and ran through their battery of tests. Eventually I ended up mailing the machine back to them for repair. A few days later, the machine showed up again with a little piece of paper saying that they couldn?t find anything wrong with it! Dang it! There is something wrong with this thing! Why didn?t they call me first before sending it back? So I decided to so a little digging on my own instead and have come up with some interesting results.

As it turns out, all of the LANs I use employ 802.1Q VLAN tagging. I suppose this is because I?m heavily into VoIP these days and separation of VoIP and Data networks is usually done with 802.1Q VLANs. This is true on all the LANs I use at work and home, but of course isn?t true when I forgo the LAN and connect directly from machine to machine. I have been able to demonstrate this quite effectively by connecting my MacBook to a switch without VLAN tagging. After plugging another host into that network, I can happily ping back and forth all day long with 0% packet loss. However, when I plug the uplink into my Cisco switch, which uses VLANs, pings are immediately sporadic and packet loss goes sky high.

This is, presumably, a software issue though it doesn?t really make sense that an X86 compiler instead of a PowerPC compiler would create such a bug. About the only thing I can come up with is that this is either some very unlikely hardware bug, or the two machines use differient Ethernet hardware and there is a problem in the new Ethernet driver.

I decided to do a little detective work and find out exactly what manufacturer makes the Ethernet hardware in the MacBook Pro. A search on the first part of my MAC address comes up with Apple Computer. That?s not very helpful because a search on the MAC address of my old PowerBook comes up with the same thing. (Apple has 13 MAC address ranges as of the writing of this story.) It looks like I?d have to crack my MacBook Pro open to find out who makes the Ethernet. I?d say there?s a very strong chance that it is a different manufacturer than the Ethernet in the PowerBook, so maybe the driver idea isn?t far off. So much for my detective work.

So what?s a good workaround if you have VLAN traffic on your LAN? Well, you could wall yourself off somehow by camping out on a LAN behind a NAT device. An AirPort would work well for this as would an old Linksys ?router?. I?m probably going to ?borrow? a VLAN aware switch and hard-set the port to non-VLAN and see if that works. In the meantime, I hope Apple announces a software update that fixes this or I?m going to have to give this thing back. Ethernet is probably the most important thing I plug into the side of my Mac. Without that, I?m going back to my PowerBook.

Comments (20)

Inga from

Dont give it back :)

Michael Tindall from Raleigh/NC/USA

I TOLD you not to buy a Gen 1. I bought my Power Book G4 gen 1 and was plagued with display and various other problems. While I firmly believe in the Apple product I have learned my lesson. NO more gen 1's. I'll leave that to the suckers....oops.

Anders from RTP

Well, I guess that's the price I pay for being an early adopter. I'm fairly confident they will fix this soon as it seems to be driver related. I am still a fan though. The speed of the thing, the full screen 1080p HD video without dropping a frame and the fact that you can dual-boot Windows XP and Mac OS X makes this thing compelling.

Anders from RTP

Looks like Apple is starting to release some fixes for the hardware issues. Of course I think my issues are driver related...

Anders from RTP

Either Apple's 10.4.6 OS update or the 1.0 Firmware update fixes this problem. I tend to think the 10.4.6 update is the one that will fix it because I believe this was a driver problem but I'm not sure. Anyone out there know?

Anders from RTP

OSX 10.4.6 update fixes this Ethernet issue.

gdam from Atlanta/ Georgia/ USA

Well I have a first generation dual core with 10.4.7 and I am having ethernet problems. It does not see the cable. I have have a regular MacBook Dual Core that does not have a problem.

This is not cool at all. I think it is driver since I loaded Win and it first started in Win mode then it began to happen in Mac.


Anders from RTP

Doesn't sound like a driver issue if your machine went from working to not working. That sounds more like a hardware issue to me.

Penrod from Omaha, NE, USA

Ethernet on my MacBook Pro Core 2 duo intel keeps dropping out. Restart usually gets it going again?for a few minutes. Once it drops out, a restart is the only way to get the ethernet functioning again.

Everything else on the hub (2 other Macs,laser printer, DSL modem) works perfectly. Cable replacement doesn't affect the flaky performance, nor does changing the hub socket or removing other devices.

OSX v. 10.4.8

Anders from RTP

Sounds hardware-ish. I'd take it to the Apple store and see what they say. Doesn't sound like a common problem.

kate from rome, italy

i have a macbook.. my ethernet has been working fine with the modem at my residence for months.. but just last week i unplugged the yellow ethernet cable and when i plugged it back in it stopped working.. i have tried restarting the mac, turning on and off the modem.. and reseting the modem and still nothing. at the control panel under network, i have activated the ethernet and renewed the lease and still nothing. the settings are on automatic.

i have no idea whats wrong or how to solve this problem. others in the building are working fine, i have been using the modem for internet for months and it's been fine. i have gotten a new modem cuz the guy said maybe its not working cuz i reet the modem but the new one is not working either. the lights on the modem= there are four- are all lit up (DSL, Internet, and power) except for the Ethernet light.

Please help me.. let me know if you might be able to help.. I saw on the posts that doing the update would work.. how do i update? is it the same update as the firmware update? (i am performing that right now)

thanks so much everyone!

Anders from RTP

Kate, it looks like your problem is NOT what I am covering in this story. Because you don't get an Ethernet light on your DSL adapter, chances are it is a hardware problem with your Ethernet. The easiest thing to try is to change your Ethernet cable. Beyond that, try plugging your computer into someone else's DSL adapter and someone else's computer into your DSL adapter and see what you get. This should help narrow it down. It does look more like a physical problem than anything else. I'd also suggest you drop by the Apple store but I don't know if they have one in Rome yet.

kolin macaulay from scotland

hi, i have the same problem, did you ever get it fixed? did you find a driver to download?cheers kolin

James Dylan from Doha, Qatar

This is really weird. I have a 17" MBP, suddenly internet connection through ethernet doesn't work. When I go to network prefs, it says it is connected and green, but when I go to Diagnostics, it spins for awhile, then the lights for "internet" & "server" go red. However, if I bring my Dell PC in and hook it to the same ethernet cable, it works fine, so the connection and cable are good.

I took the Mac to a different cable and connected it, same thing. However, wireless works (which is what I am using now). zapped PRAM, too. Long story short; I reformatted the mac, zeroed out the HD and reinstalled OS 10.5, everything is updated, but....internet via ethernet jack still doesn't work. I don't know how this could be a software issue when I did a totally clean install. Is my ethernet jack faulty? I'm at the end of the line, don't know what else to do. Simply can't get it to work. PC works fine though on same connections.

Any help?

Anders from RTP

James: Sounds like your Ethernet hardware is broken. There is a chance it got zapped electrically if it once worked and now does not after a software re-install. I'd say you should take it to an Apple store but that's probably a long drive for you in Qatar. There may be USB dongle type Ethernet adapters you could try though I have no experience with them.

Jeremy from Zeeland / Michigan / USA

I have been having a similar issue with my MacBook Pro - OS 10.5.4 - I am using a simple Linksys 10/100/1000 switch, and I've found that when connected through the switch to a host which is using 100Mbit hardware, I drop packets like crazy. When I force the Ethernet connection speed to 100baseTX in Network preferences I do _not_ get this behavior... it almost seems as though the interface has difficulty translating between packet transmission speeds which could be a driver issue, or a hardware issue. The chipset used in the MacBook Pro seems to be the Marvell Yukon2 10/100/1000Base-T it that helps you out any :-)

Please let me know if you've heard of any fixes to this problem!

Jaco from Windhoek, Namibia

A client of mine has a macbook Pro, with some weird LAN issues, the cable is pluged in and the DHCP configures the ip correctly but i can't ping the router or any other machines on the network. wifi works fine. restart the mac, and it works for a while and then again, lan is correctly configured but no data goes through. what can it be?

Anders from Cambridge, MA

Jaco: Do you loose link support? (Does the link light stay on on the switch?) It sounds like a hardware problem but you could try a reinstall on the off chance it is driver related.

Rishikesh from India

I have a Macbook Pro with intel core i5. i used to play online games on my mac and it was working just perfectly fine. now suddenly the game stopped working because i'm getting 40% packet loss. I plugged in my windows laptop and works just fine. I'm running on OS X 10.9.5. So is it a problem with my hardware?

Anders from Cambridge, MA

Apple fixed this some time ago. Was there anything you changed before you started seeing packet loss? You might consider reinstalling the OS.

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