1Gbe Ethernet running as 100Mbe.


podcake

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I have an Asrock Z77 Extreme4 Motherboard running a Broadcom BCM57781 10/100/1000 Mbps Ethernet Controller.
Booting into a Windows PE, or any OS other than unRaid, the ethernet will auto-negotiate 1Gbps. However, in unRaid, the ethernet negotiates 100Mbps after failing negotiating 1Gbps. 


The System Log shows this:

image.png.063c72ef7e21eda2b6773152fa14efe7.png

 

I have an extra 4-port 1Gbe Intel Card, however it won't even get link status while in unRaid. unRaid reports the extra ethernet adapters, but plugging a cable in does not do anything. No lights come on the NIC. 
image.png.87e376a3190a04d041c3b87bd2b6cd11.png

 

The Server is plugged into a 5-port Gigabit Unmanaged Switch, and it negotiates 100Mbps no matter the Port or Cable used. If I plug the server directly into the wall it also negotiates 100Mbps.

I'm kind of lost on where to go from here. I thought the 4-port network card would at least help me diagnose if it's a hardware or software problem, but since I can't even get it working, or even exhibit the same behavior as the Built-In Motherboard NIC.

 

If you need anymore information of copies of logs let me know :)

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Go to console and type ifconfig and paste a screenshot of the eth0: stats. If it is 100, then you might need to use ehtool to change the settings in Unraid. Reason you get get something different in a linux environment from a windows environment may just be a setting in the linux environment in unraid.

 

Unless someone else has a better solution...that's my guess.

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3 minutes ago, podcake said:

ifconfig dump:
image.png.1789c3ddc424ef6b46915ab435178b29.png

 

This is the dump i get from ethtool etho0
image.png.f43dec709acd71815f10289ade362506.png

Manually setting the Link Speed to 1000 caused the link to be dropped.

 

So I think it's a negotiation issue between unRaid and the NIC on my motherboard, that other OSes don't run into.

I had to force restart my server, and after starting back up it's still in 100Mbps mode.

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1 minute ago, itimpi said:

It could be caused by the cabling (or possibly even a port).    100Mb Ethernet needs less working connections in a cable than 1GB Ethernet.

I've ruled that out. Not only is it 100Mbps no matter what cable I use, it doesn't even matter what port on the switch I use. And if I plug it directly into the wall, it's still 100Mbps.

I *can* get 1Gbps by connecting a cable directly from my desktop to my server. But using that exact cable to go to the wall or the switch results in 100Mbps.

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10 minutes ago, podcake said:

I've ruled that out. Not only is it 100Mbps no matter what cable I use, it doesn't even matter what port on the switch I use. And if I plug it directly into the wall, it's still 100Mbps.

I *can* get 1Gbps by connecting a cable directly from my desktop to my server. But using that exact cable to go to the wall or the switch results in 100Mbps.

Here's your problem:
image.png.3cd79bb577488b4385640baff419db51.png

The partner it is plugged into is saying it only supports 10/100 for some reason. I would double check that it is indeed a gigabit switch, and if it is - I would try a different switch in that position. I'm also working off some assumptions here. It's possible the switch is degrading all links to 10/100 because the upstream link is 10/100, though that isn't common these days.

You've already confirmed the card in the server and the cables aren't the problem - the server negotiates a 10/100/1000 link just fine when connected to a different endpoint, so the suspect is the switch, and that output confirms it. The switch is only advertising 10/100.

EDIT:

I see you say it also does that when plugged into the wall. From the wall termination, where does it go? Is the cable pulled thru the wall good? How long is that run? Has that run been tested with a cable tester? There's lots of questions here. If it works with a short cable directly between two endpoints, then the endpoints are working properly.

Edited by Xaero
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2 minutes ago, Xaero said:

Here's your problem:
image.png.3cd79bb577488b4385640baff419db51.png

The partner it is plugged into is saying it only supports 10/100 for some reason. I would double check that it is indeed a gigabit switch, and if it is - I would try a different switch in that position. I'm also working off some assumptions here. It's possible the switch is degrading all links to 10/100 because the upstream link is 10/100, though that isn't common these days.

You've already confirmed the card in the server and the cables aren't the problem - the server negotiates a 10/100/1000 link just fine when connected to a different endpoint, so the suspect is the switch, and that output confirms it. The switch is only advertising 10/100.

I thought that too, except the switch IS gigabit. I have my server, desktop, and laptop all plugged into the switch and all but the server get gigabit. 
This also wouldn't explain the 100Mbps I get if connected directly to the wall that I KNOW is a gigabit connection. (I've tested it on multiple machines and different OSes).

IMG_0480.thumb.jpeg.bc5a0d44a12ae1f15e2ef4411c5ab766.jpeg
This is my Switch Setup. 

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26 minutes ago, podcake said:

Just checked the switch in the Network Closet that links all the rooms in my apartment together, and it's a gigabit switch and every link is reporting gigabit speeds.

I might try running a 20 ft cable directly from the Server to the Network Closet Switch.

Didn't do anything. Both the Switch and unRaid report a 100Mbps connection when connected directly to the Switch in the Network Closet.

Honestly I'm lost as to what the issue is. Especially since it's not a driver issue because I can get 1Gbps between my server and desktop (5ft max).
It could be distance but then why would it negotiate 100Mbps with a 1ft cable connected my switch to my server?


At this point, I'm just gonna do ethernet from server -> desktop, accept that won't be able to access the server from outside the network, and use wifi on my desktop to connect to the internet.

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Oh, that would definitely indicate that the switch itself is fine.

It looks like something changed between Linux Kernel 4.14 and 4.15 that probably caused an issue with all chips in the TG3 driver:
https://askubuntu.com/questions/1163256/broadcom-bcm5764m-gigabit-ethernet-wont-connect-at-gigabit-speed

That chip is indeed covered by the TG3 driver:
https://linux-hardware.org/index.php?id=pci:14e4-16b1-17aa-3975

And that would line up with your experience of "Works in Windows, but not here."

Edited by Xaero
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6 minutes ago, Xaero said:

Oh, that would definitely indicate that the switch itself is fine.

It looks like something changed between Linux Kernel 4.14 and 4.15 that probably caused an issue with all chips in the TG3 driver:
https://askubuntu.com/questions/1163256/broadcom-bcm5764m-gigabit-ethernet-wont-connect-at-gigabit-speed

That chip is indeed covered by the TG3 driver:
https://linux-hardware.org/index.php?id=pci:14e4-16b1-17aa-3975

And that would line up with your experience of "Works in Windows, but not here."

Yea that article on AskUbuntu lines up PERFECTLY with my issue.

I don't know how unRaid handles a manual linux kernel upgrade, but I imagine not well, so it's probably best I wait for LimeTech to update unRaid to include a new kernel that *hopefully* fixes my issue.

I'm already running the beta 6.10.0-rc1 so I guess I'll just deal with the 100mbps speed until a fix comes out or I upgrade my system.
It is 3rd gen intel, and it is well due for an upgrade. :)

Thanks for the help!

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Just now, podcake said:

Yea that article on AskUbuntu lines up PERFECTLY with my issue.

I don't know how unRaid handles a manual linux kernel upgrade, but I imagine not well, so it's probably best I wait for LimeTech to update unRaid to include a new kernel that *hopefully* fixes my issue.

I'm already running the beta 6.10.0-rc1 so I guess I'll just deal with the 100mbps speed until a fix comes out or I upgrade my system.
It is 3rd gen intel, and it is well due for an upgrade. :)

Thanks for the help!


No worries -
You could try this workaround that is reported to fix many issues with that chipset -- but YMMV as none of them mention this gigabit negotiation issue:
https://wiki.archlinux.org/title/Network_configuration/Ethernet#Broadcom_BCM57780

If it works, you can also make that change permanent until such time that a Kernel mainline fix arrives.

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On 9/14/2021 at 5:14 PM, Xaero said:


No worries -
You could try this workaround that is reported to fix many issues with that chipset -- but YMMV as none of them mention this gigabit negotiation issue:
https://wiki.archlinux.org/title/Network_configuration/Ethernet#Broadcom_BCM57780

If it works, you can also make that change permanent until such time that a Kernel mainline fix arrives.

Ok i'll try that. I'm doing fine with just directly connecting my server to my desktop, although that means my VMs can't access the internet anymore.

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46 minutes ago, JonathanM said:

Why not? Assuming your desktop has internet.

I have my server connected to my Desktop via Ethernet. And then i have my Desktop connected via WiFi.

I tried setting up a bridge in Windows between the Ethernet and WiFi but it broke the access to the server.

Maybe i'm doing something wrong, but my server and desktop only have 1 ethernet port

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  • 11 months later...

9/14/22

UPDATE: Bought a new nic card and placed in the server. Works like a charm. Guess maybe my onboard nic is bad???

 

----------------

8/21/22

Hey guys. Newbie here. Been reading this post and trying various things from it. I am having similar issues.

I am running Unraid 6.9.2. 

I have a Realtek Semiconductor Co., Ltd. RTL8101/2/6E PCI Express Fast/Gigabit Ethernet controller onboard that is running at 100Mbps. 

I am including my diagnostic file to help. triton-diagnostics-20220821-1842.zip

I have tried restarting the server, changing the network cable, plugging into a different port on the router.

Main router is pfsense. then I have a Netgear R6220 for my switch and wireless AP. 

All other devices on my R6220 have gigabit connections except my server. 

I tried upgrading to Unraid 6.10.3. Did not change a thing except that my VM will not start with the passthrough video card. (I know. Different problem)

 

Any help will be greatly appreciated.

Thank you in advance,

Jeff

Edited by lovingit77
Updated the post with new information
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