Network connection issues no-carrier

luftruessel

New Member
Mar 25, 2024
2
0
1
First: The cable is connected properly and working - I used it successfully on other hardware. The port is working, the status LEDs are on, and the whole connection worked a few weeks ago. But I'll start from the beginning:

A few weeks ago, I set up my (almost) first Proxmox server. Version 8.1 on a Topton N5105 NAS Board. I got everything running (including the network). After that I went and set up some LXCs, HDDs and the usual. Everything was fine, rebooted the thing a couple of times or turned it off over night and it came back fine. Used it for about 2 weeks like this. I went out of town for a week and when I came back, the system did not start properly. In the sense, that I can not reach it via the Web Interface. At first I thought it was a boot issue, but connecting a monitor and keyboard it boots and tells me it is available on port 8006. I do get an error about the zfs pool initialization, which I can provide further info about if anyone thinks this might be related. But since I can't reach the system in any useful way at the moment, I set my priority on getting it back online first.

This is when I started digging. I did not feel like just resetting the system, because this was the second time this happened! Weeks before the first setup, the same thing happened where I could not reach it in the network (thinking about it, I also got the z pool error then!). So what connected the two cases: It was offline for a few days before it happened, I also got the zpool error, and I had installed Openwrt before that!

So what did I figure out? I will attach what I tried so far.
looked at /etc/networking/interfaces which looks like this:

WhatsApp Image 2024-03-25 at 19.14.58.jpeg

I checked
Code:
ip addr
which looks like this:
WhatsApp Image 2024-03-25 at 19.14.59.jpeg
enp2s0 is the Ethernet Port which I use atm (and which I used all the time when it was working). I also tried all the other ports but there is no difference - they will all state no-carrier when attaching the ethernet cable. Both status LEDs of the port a on, green is blinking, but not very much, orange is always on. I tested the cable on another device and its fine.

I found out that I have the I226-V Ethernet Controller, which seems to have quiet some issues. But I can not set the speed, neither the Duplex with the ethtool because it says no-carrier anyway.

I noticed that the IP is within the DHCP range of my router, which may or may not be a problem. I moved the range and also rebooted the router (Fritzbox).

Also I checked the journal, but the network seemed to come up just fine (not that I was able to properly judge)
WhatsApp Image 2024-03-25 at 19.27.02.jpeg

Bridge did some status changes, but the errors I see are about the zpool only. I also did some research around that, but could not figure it out (and like I said, not reaching the network seemed like a bigger issue to me.

/etc/hosts looks like this:
WhatsApp Image 2024-03-25 at 19.34.29.jpeg

Lastly I tried installing OpenWRT last before that whole thing started, but I think to remember that I was able to reboot it with OpenWRT installed. However the OpenWRT container, as well as the bridge vmbr1 which I created for it were deleted during debugging.

Let me know if any other input about my setup is required. Thanks for reading
 
First: The cable is connected properly and working - I used it successfully on other hardware. The port is working, the status LEDs are on, and the whole connection worked a few weeks ago. But I'll start from the beginning:

A few weeks ago, I set up my (almost) first Proxmox server. Version 8.1 on a Topton N5105 NAS Board. I got everything running (including the network). After that I went and set up some LXCs, HDDs and the usual. Everything was fine, rebooted the thing a couple of times or turned it off over night and it came back fine. Used it for about 2 weeks like this. I went out of town for a week and when I came back, the system did not start properly. In the sense, that I can not reach it via the Web Interface. At first I thought it was a boot issue, but connecting a monitor and keyboard it boots and tells me it is available on port 8006. I do get an error about the zfs pool initialization, which I can provide further info about if anyone thinks this might be related. But since I can't reach the system in any useful way at the moment, I set my priority on getting it back online first.

This is when I started digging. I did not feel like just resetting the system, because this was the second time this happened! Weeks before the first setup, the same thing happened where I could not reach it in the network (thinking about it, I also got the z pool error then!). So what connected the two cases: It was offline for a few days before it happened, I also got the zpool error, and I had installed Openwrt before that!

So what did I figure out? I will attach what I tried so far.
looked at /etc/networking/interfaces which looks like this:

View attachment 65277

I checked
Code:
ip addr
which looks like this:
View attachment 65278
enp2s0 is the Ethernet Port which I use atm (and which I used all the time when it was working). I also tried all the other ports but there is no difference - they will all state no-carrier when attaching the ethernet cable. Both status LEDs of the port a on, green is blinking, but not very much, orange is always on. I tested the cable on another device and its fine.

I found out that I have the I226-V Ethernet Controller, which seems to have quiet some issues. But I can not set the speed, neither the Duplex with the ethtool because it says no-carrier anyway.

I noticed that the IP is within the DHCP range of my router, which may or may not be a problem. I moved the range and also rebooted the router (Fritzbox).

Also I checked the journal, but the network seemed to come up just fine (not that I was able to properly judge)
View attachment 65281

Bridge did some status changes, but the errors I see are about the zpool only. I also did some research around that, but could not figure it out (and like I said, not reaching the network seemed like a bigger issue to me.

/etc/hosts looks like this:
View attachment 65282

Lastly I tried installing OpenWRT last before that whole thing started, but I think to remember that I was able to reboot it with OpenWRT installed. However the OpenWRT container, as well as the bridge vmbr1 which I created for it were deleted during debugging.

Let me know if any other input about my setup is required. Thanks for reading
Hey @luftruessel
Did you ever find a solution to this? I'm have a similar issue.
 
Hey @luftruessel
Did you ever find a solution to this? I'm have a similar issue.
Thanks for reminding me, I have been wanting to come back to this for a while.
I did a reset of my whole system and it has been running fine for some time now, so I am rather confident that it is working now. This is not very much of a solution, but I have a suspicion of what might be the (=my) issue and that might help to fix it by changing networking/interfaces.

So here is what I did before the reset: I got some USB Device with bootable Ubuntu. Sure enough, on the same hardware ofc, Ubuntu got a working network connection. And looking at the interfaces (or whatever manages the networking devices in Ubuntu) file, the name of my bridge and working ethernet port were different. So let's say enp3s0 was my working interfaces instead of enp2s0, even though I never switched the physical cable.

I have no idea if this was the real reason and I just failed to configure it properly in my Proxmox interfaces file (due to my poor understanding of the whole thing), or it was something different all along. Someone more qualified might be able to tell if these names (in my understanding they are just names) are something that might change due to driver updates or whatever. Maybe I just messed something else up during setup.

Get some bootable OS and have a look at that to make sure your hardware is fine might be the best advice I am able to give. Maybe also provide some more info about your errors/config
 
Last edited:

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