[SOLVED] No network connectivity after Fresh Proxmox 7 install

R

Razva

Renowned Member
Dec 3, 2013
252
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83
Romania
cncted.com
Hey,

I'm doing a fresh install of Proxmox 7 via the official ISO.

The installation finishes without any issues, server boots as expected, the NIC is listed, network settings are successfully applied.

But unfortunately, even if everything seems to be fine, I have no network connectivity. I can't even ping the gateway.

Please note that the same machine has zero networking issues if upgraded from 6 to 7. The aftermentioned issue is only when doing a fresh ISO install.

Any hints? Where should I start looking? What logs are necessary in order to debug this?

Thank you
 
I came in to ask same thing. Have tried upgrade and fresh install, neither has network connectivity. I should say both of my are into a VM on Hyper-V, which is my third machine in my quorum without intention of hosting other vms.
 
Solved it by adding the following line under iface vmbr0 inet static in /etc/network/interfaces
hwaddress XX:XX

The XX:XX is the full mac address of the physical interface.
 
I upgraded to 7 with apt. The installation went well but after reboot, I had no network connectivity. I use Intel i219-LM on a ThinkCentre M90n. After the reboot, e1000e complains that it couldn't probe the interface and errored with -2. Backed up my data over USB and then formatted and reinstalled Proxmox 7 with iso. Installed alright but e1000e cannot probe. I formatted and installed Proxmox 6.4 latest iso, apt update (with the iso's apt repos) and everything still works after a reboot. If I add the no-subscription repo and apt upgrade, upon reboot, the same problem happens. I then went back to the EFI bootloader and selected the old kernel and this kernel also shows the problem. There are only a few packages which are upgraded from the iso to the latest, but the same problem happens for me on Proxmox 6, so maybe a recent & common change in Proxmox? Because it cannot probe the interface, it doesn't show me the adapter in `ip addr` but I do show the network adapter when I run lspci. Read a variety of articles that say it's probably WOL features but I disabled that capability in the BIOS and still couldn't get the adapter to come up.
 
Last edited:
Razva said:
Is there any fix/feedback from Proxmox Staff? It seems like a common issue. Thank you
Click to expand...
Are you in a restricted network that restricts MAC-addresses a server can use, e.g., like the environments of hosting provider often do?

VLAN or some settings like that, that were still configured on the upgraded host but not yet on the fresh installed one?
 
t.lamprecht said:
Are you in a restricted network that restricts MAC-addresses a server can use, e.g., like the environments of hosting provider often do?

VLAN or some settings like that, that were still configured on the upgraded host but not yet on the fresh installed one?
Click to expand...
Nope, none of above. When installing any other distro, including Proxmox 6, everything works as expected.
 
Yes please, the following exhaustive information could be of help:

Code: 
ip -d addr
ip ro
lspci -knn
cat /etc/network/interfaces

to get an overview and rule a few things out, if we're lucky it's just a little, overlooked config error - would prefer that over some weird difference between upgrade/fresh installation :)
 
t.lamprecht said:
Yes pleas, the following exhaustive information could be of help:

Code: 
ip -d addr
ip ro
lspci -knn
cat /etc/network/interfaces

to get an overview and rule a few things out, if we're lucky it's just a little, overlooked config error - would prefer that over some weird difference between upgrade/fresh installation :)
Click to expand...
Ok, I'll do screen grabs from IPMI, as I can't paste from CLI. :) Is that OK?
 
t.lamprecht said:
I like text better, but screenshots are still better than nothing :)
Click to expand...
I'm using Hetzner so I can't think of any way of exporting text from their IPMI without internet access on the host. If you have any ideas please let me know. Right now I'm waiting for them to activate my IPMI.
 
Razva said:
I'm using Hetzner
Click to expand...
But then you are in a restricted, hosting provider environment?
t.lamprecht said:
Are you in a restricted network that restricts MAC-addresses a server can use, e.g., like the environments of hosting provider often do?
Click to expand...

I'd suggest trying to set the MAC address on the bridge to the one of it's physical bridge-ports, as described in the upgrade how-to:
https://pve.proxmox.com/wiki/Upgrade_from_6.x_to_7.0#Check_Linux_Network_Bridge_MAC
 
t.lamprecht said:
But then you are in a restricted, hosting provider environment?


I'd suggest trying to set the MAC address on the bridge to the one of it's physical bridge-ports, as described in the upgrade how-to:
https://pve.proxmox.com/wiki/Upgrade_from_6.x_to_7.0#Check_Linux_Network_Bridge_MAC
Click to expand...
Well yes, I am, but the same restrictions apply when using Proxmox 6 without any issues. So the fact that right now 6 works as expected (along with Debian 10, plus Hetzner's rescue system) proves that there's nothing wrong with the machine, network and/or settings.

Or am I wrong?

Anyway, I'll add hwaddress in the config and give it a try.
 
Last edited:
I'm just curious, how could I get the initial/real MAC address on a fresh 7 install? Because booting a Live OS just to get a MAC address is OK for 1-2 machines, but not for 10+.

Later edit: here's the current Proxmox 6 config.
 
Last edited:
Razva said:
Well yes, I am, but the same restrictions apply when using Proxmox 6 without any issues. So the fact that right now 6 works as expected (along with Debian 10, plus Hetzner's rescue system) proves that there's nothing wrong with the machine, network and/or settings.

Or am I wrong?

Anyway, I'll add hwaddress in the config and give it a try.
Click to expand...
The MAC-Address policy changed between the systemd used by PVE 6.x and PVE 7.x, see the following upgrade how-to section for details: https://pve.proxmox.com/wiki/Upgrade_from_6.x_to_7.0#Linux_Bridge_MAC-Address_Change

So, in PVE 6.4 your bridge always had the MAC of the (physical) port, which is probably the one that's allowed from Hetzners firewall rules. With 7.0 it gets another one by default, Hetzners firewall does not recognize that MAC as allowed -> blocked (to avoid MAC spoofing, some dedicated-server hosting prodivers also may use VXLAN/VLAN and could be more relaxed regarding MACs).

Any how, that's why you need to set it static to the one from the port, at least if you're in a restricted network (normally everything where the switch config is not under your (companies) control).

FYI: If you setup a Debian 11 Bullseye, or any other modern Distro like a Fedora 33 or Ubuntu 21.04 and setup a bridge then you'll see the same behavior, this is not directly Proxmox VE specific, but as PVE pretty much always uses Linux bridges that changes is felt more.
 
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t.lamprecht said:
The MAC-Address policy changed between the systemd used by PVE 6.x and PVE 7.x, see the following upgrade how-to section for details: https://pve.proxmox.com/wiki/Upgrade_from_6.x_to_7.0#Linux_Bridge_MAC-Address_Change

So, in PVE 6.4 your bridge always had the MAC of the (physical) port, which is probably the one that's allowed from Hetzners firewall rules. With 7.0 it gets another one by default, Hetzners firewall does not recognize that MAC as allowed -> blocked (to avoid MAC spoofing, some dedicated-server hosting prodivers also may use VXLAN/VLAN and could be more relaxed regarding MACs).

Any how, that's why you need to set it static to the one from the port, at least if you're in a restricted network (normally everything where the switch config is not under your (companies) control).

FYI: If you setup a Debian 11 Bullseye, or any other modern Distro like a Fedora 33 or Ubuntu 21.04 and setup a bridge then you'll see the same behavior, this is not directly Proxmox VE specific, but as PVE pretty much always uses Linux bridges that changes is felt more.
Click to expand...
Thank you for the in-depth explanation! So basically I should get the MAC address of the physical NIC and use it on the bridge as well. Correct?
 
We tried to convey it quite explicitly in the upgrade how-to, and that how-to is heavily recommend getting read and followed closely before and during upgrade, to avoid as many pitfalls on the way.
But we'll see if we can further improve this, possibly adding a hint to the pve6to7 checker script.
 
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