VMs not getting DHCP response and are unaccessible

timbrook

New Member
Jan 14, 2021
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tl;dr same config on different machines, different results. How to debug?

This is all with a fresh install of 6.3 downloaded today. I've installed on a Aorus Pro AX Z490 board and am using the onboard NIC.

After install I set the net interface to DHCP

Code:
auto vmbr0
iface vmbr0 inet dhcp
    bridge-ports enp5s0
    bridge-stp off
    bridge-fd 0

I've tried setting gateways, subnets and as well a static ip. All end up with a working host that I can connect to. But the same issues as follows.

Created a VM, enable qemu, add a network card (tried all of them) and boot into a ubuntu live. This was my test, the first attempt was with win10. Fails to get an IP, but I can see broadcast traffic and my ubiquity USG sees the request for IP. And thats it, never get anything back to the VM. I think this is something to do with the NIC on the motherboard. I installed the exact same config on a 2018 mac mini and it works flawlessly.

So here's my question. What should I be looking for to debug this?? I've spent a few days on this now (part time) and can't seem to make any progress.
 

timbrook

New Member
Jan 14, 2021
3
0
1
27
This is what I'm working with now, i'd like to go back to using dhcp if possible as well.

Code:
# cat /etc/network/interfaces
# network interface settings; autogenerated
# Please do NOT modify this file directly, unless you know what
# you're doing.
#
# If you want to manage parts of the network configuration manually,
# please utilize the 'source' or 'source-directory' directives to do
# so.
# PVE will preserve these directives, but will NOT read its network
# configuration from sourced files, so do not attempt to move any of
# the PVE managed interfaces into external files!

auto lo
iface lo inet loopback

auto enp5s0
iface enp5s0 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.1.201
        netmask 255.255.255.0
        gateway 192.168.1.1
        bridge-ports enp5s0
        bridge-stp off
        bridge-fd 0

This is my test vm as well.
Code:
# cat /etc/pve/qemu-server/100.conf
agent: 1
boot: order=scsi0;ide2
cores: 8
ide2: local:iso/ubuntu-20.04.1-desktop-amd64.iso,media=cdrom
memory: 8096
name: virtio-test
net0: virtio=C6:91:B6:BD:4B:E9,bridge=vmbr0,firewall=1
numa: 0
ostype: l26
scsi0: local-lvm:vm-100-disk-0,size=32G
scsihw: virtio-scsi-pci
smbios1: uuid=6c44fcfc-e970-4b97-8dcd-9ac7d2a9a775
sockets: 1
vmgenid: b12576d5-d8bd-4ab0-80e5-aa8afe8344b2
 

timbrook

New Member
Jan 14, 2021
3
0
1
27
can you ping the node from your VM?
No I never get an IP in the VM. Tried regardless and get Network unreachable as expected. Gave the VM a static IP on the same subnet and was still unable to ping. Just host unreachable.
 

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