Apple Event: May 7th at 7 am PT
Early 2008 Mac Pro with 16G RAM. Ethernet Ports (both ports) stop occasionally. Reboot always brings them back to normal. OSX version irrelevant - has been ongoing over several major updates.
Ports when stopped appear normal and change of config or turning them off and back on does not help. Only a reboot will bring them back. I can not correlate any specific activity or software to the problem - appears random.
Mac Pro, OS X El Capitan (10.11.4)
Hello, me again.
I just wanted to give a update on this issue, since i've been continuing to tackle it. I really think this is a driver issue that is neglected by Apple. I recently abandoned macOS on the Mac Pro 3,1 since it is not supported beyond El Capitan, and installed Windows 10 straight up without using boot camp on the 2nd internal disk using a Windows 10 DVD. Well guess what, the ethernet ports are working just fine and dandy for well over a month now. I realize that this is probably not a solution for most people here but i thought i would point out that discovery. For my purposes, all the apps i need to use are also available for windows. On the hardware side, everything seems to work perfectly on the Mac Pro with Windows 10 except the built in speaker and built in bluetooth, but for my purposes as a headless server, that's a non-issue. I much prefer the stability.
What i had been doing before installing windows 10 is i had setup an automator script that would make the ethernet ports inactive and active again, twice a day. My specific issue would get resolved simply by going into system preferences and making the afflicted ethernet interface inactive, then active again. So with an automator script running on the calendar app every 12 hours it was as close as i could get to having consistent network uptime. But then came the time that the ethernet port failed soon after the script had run, and there was a downtime of almost 12 hours. So to **** with the workaround and hacks, i decided to give Windows 10 on the Mac Pro a try as i found a few articles online saying it worked well. I'll give it a few more weeks and then i'll wipe the 1st disk with macOS on it and use the space for Windows.
I used to have more macOS machines running in the house than Windows, this install just turned the tide.
So far i've tried the solution posted in the first post on page 7 of the following thread, from user kickmyass: Ethernet has a self-assigned IP address and will not be able to connect...
i.e. deleting com.apple.alf.plist and rebooting the mac pro.
I'm not going to keep my hopes up but so far so good, ethernet port is fine, for almost two weeks, i think... Will post back if I see the issue again.
Other things i've done for the time being is connect the 2nd ethernet port and the wifi to the same network for redundancy. Network settings is configured to use Ethernet 1 as the primary network, and the router is routing outside traffic to Ethernet 2. In my situation this makes most of the traffic go through Ethernet 1 and so if Ethernet 1 starts breaking (self assigned ip symptom) at least my services for outside traffic still works, OS X will now use Ethernet 2 for all of its traffic and it gives me time to realize the problem is creeping up and reboot the machine before Ethernet 2 goes down. Wifi is there in the case both ports die really fast, since the machine is headless, so i can still remote in and reboot it as a last resort.
If deleting com.apple.alf.plist doesn't work, I'm going to give up. At least i have some sort of redundancy working on the network.
My instances have slowed down considerably. As I mentioned before, hooking up the 2nd ethernet port does not help my situation. I can turn on WiFi but that is not a fix for me - reboot remains the only fix. Not sure why the issue is happening less often unless one of the El Capitan updates has helped.
I've been having the same experience for about a year. I've got a Mac Pro running El Capitan, but I think this was happening with previous OS X versions.
Testing so far.
If I try and copy a large amount of data (e.g. a 40GB VM) to my TC, this will trigger the behaviour within a minute or so.
If I connect to the TC using SMB (not AFP), then the connection appear more stable. The issue with SMB vs AFP is SMB enforces maximum file size limits.
If I reboot this restores the ethernet connection.
If I disable (make connection inactive, then active) this also restores the connection.
When the fault presents, the Mac thinks it's still connected, there is just no traffic flow. If I try and PING anything, no response.
Have also tried static IP addresses, using either ethernet port. Same behaviour.
It's like the TCP/IP stack plus the AFP client can't handle large file transfers.
A large transfer will sometimes trigger my problem but can't say that is the cause because it will occasionally happen with little activity. Also my ethernet activity can be a web download or inside my own network - there is nothing I can point to specifically. Reboot is my ONLY option but reboot always works. I normally use static IPs throughout my network but have tried DHCP with same results. The way I'm reading this, there must be several concurrent issues because of the various triggers and various solutions.
It's interesting as I only noticed in the past few weeks the ethernet ports on my Mac Pro (Early 2008) running El Capitan had self-assigned IP addresses. I only use one port, and switching to the other gave me the same result. I only noticed as I turned off Wi-Fi on the Mac Pro and then couldn't VNC remotely.
Just before coming here I found the com.apple.alf.plist trick and tried that. Not sure if it will cure it, but I note the last modified date was in 2011, to the day (but not hour)...
Anyway, so far it's doing what a reboot has done prior to this - given me back a reserved IP address. Will see how long it lasts.
I have not had the issue since i deleted com.apple.alf.plist , however, i've had to reboot my mac pro (early 2008) for other reasons since i did that, mainly software updates and such.
So far so good.
I got the self-assigned ip address issue yesterday. I am giving up. Good luck with your respective issues, I may check this thread from time to time to see if any advancements have been made.
Ethernet Ports Stop Working
