VM Network Traffic is visible to all VM in the same VLAN, but only if they are using VirtIO Network Bridge

Noah0302

Member
Jul 21, 2022
57
8
8
Hello guys,

I am currently facing an Issue in our Proxmox Cluster as described in the Title.
It does not matter on which Node the VMs are on, or if they run Linux or Windows, it happens on every single one.
However LXCs in the same VLAN are not affected, since they dont use the VirtIO Adapter, as far as I can tell.

Here are some Infos on the current Setup:
Pakage Versions on each Node:
Code:
proxmox-ve: 7.4-1 (running kernel: 5.15.108-1-pve)
pve-manager: 7.4-18 (running version: 7.4-18/b1f94095)
pve-kernel-5.15: 7.4-14
pve-kernel-5.15.158-1-pve: 5.15.158-1
pve-kernel-5.15.131-2-pve: 5.15.131-3
pve-kernel-5.15.131-1-pve: 5.15.131-2
pve-kernel-5.15.108-1-pve: 5.15.108-2
pve-kernel-5.15.30-2-pve: 5.15.30-3
ceph: 16.2.15-pve1
ceph-fuse: 16.2.15-pve1
corosync: 3.1.7-pve1
criu: 3.15-1+pve-1
glusterfs-client: 9.2-1
ifupdown2: 3.1.0-1+pmx4
ksm-control-daemon: 1.4-1
libjs-extjs: 7.0.0-1
libknet1: 1.24-pve2
libproxmox-acme-perl: 1.4.4
libproxmox-backup-qemu0: 1.3.1-1
libproxmox-rs-perl: 0.2.1
libpve-access-control: 7.4.3
libpve-apiclient-perl: 3.2-2
libpve-common-perl: 7.4-2
libpve-guest-common-perl: 4.2-4
libpve-http-server-perl: 4.2-3
libpve-rs-perl: 0.7.7
libpve-storage-perl: 7.4-3
libspice-server1: 0.14.3-2.1
lvm2: 2.03.11-2.1
lxc-pve: 5.0.2-2
lxcfs: 5.0.3-pve1
novnc-pve: 1.4.0-1
proxmox-backup-client: 2.4.7-1
proxmox-backup-file-restore: 2.4.7-1
proxmox-kernel-helper: 7.4-1
proxmox-mail-forward: 0.1.1-1
proxmox-mini-journalreader: 1.3-1
proxmox-offline-mirror-helper: 0.5.2
proxmox-widget-toolkit: 3.7.4
pve-cluster: 7.3-3
pve-container: 4.4-7
pve-docs: 7.4-2
pve-edk2-firmware: 3.20230228-4~bpo11+3
pve-firewall: 4.3-5
pve-firmware: 3.6-6
pve-ha-manager: 3.6.1
pve-i18n: 2.12-1
pve-qemu-kvm: 7.2.10-1
pve-xtermjs: 4.16.0-2
qemu-server: 7.4-6
smartmontools: 7.2-pve3
spiceterm: 3.2-2
swtpm: 0.8.0~bpo11+3
vncterm: 1.7-1
zfsutils-linux: 2.1.15-pve1
cat /etc/network/interfaces
Code:
# 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 eno1
iface eno1 inet manual
#Port 1 - 1G

auto eno2
iface eno2 inet manual
#Port 2 - 1G

auto eno3
iface eno3 inet manual
#Port 3 - 1G

auto eno4
iface eno4 inet manual
#Port 4 - 1G

iface enx0a94ef038ed7 inet manual

auto ens1f0
iface ens1f0 inet manual
        mtu 9000
#Port 1 - 10G

auto ens1f1
iface ens1f1 inet manual
        mtu 9000
#Port 2 - 10G

auto bond100
iface bond100 inet manual
        bond-slaves eno1 eno3
        bond-miimon 100
        bond-mode balance-alb
#Bond 4G

auto bond900
iface bond900 inet manual
        bond-slaves ens1f0 ens1f1
        bond-miimon 100
        bond-mode balance-alb
        mtu 9000
#Bond 20G

auto bond800
iface bond800 inet manual
        bond-slaves eno2 eno4
        bond-miimon 100
        bond-mode active-backup
        bond-primary eno2
#Corosync

auto vmbr100
iface vmbr100 inet manual
        bridge-ports bond100
        bridge-stp off
        bridge-fd 0
        bridge-vlan-aware yes
        bridge-vids 2-4094
#Bridge 4G

auto vmbr900
iface vmbr900 inet manual
        bridge-ports bond900
        bridge-stp off
        bridge-fd 0
        bridge-vlan-aware yes
        bridge-vids 2-4094
        mtu 9000
#Bridge 20G

auto vlan900
iface vlan900 inet static
        address 10.10.20.70/24
        mtu 9000
        vlan-raw-device vmbr900
#Cluster / CEPH

auto vlan20
iface vlan20 inet static
        address 172.17.20.70/24
        gateway 172.17.20.1
        vlan-raw-device vmbr100
#Management

auto vlan800
iface vlan800 inet static
        address 10.10.30.70/24
        vlan-raw-device bond800
#Corosync


The Issue does not appear in the following VM-Config:
Code:
agent: 1
boot: order=virtio0;ide2;net0;ide0
cores: 4
ide0: none,media=cdrom
ide2: none,media=cdrom
machine: pc-i440fx-7.1
memory: 4096
meta: creation-qemu=7.1.0,ctime=1682677511
name: Win10-VLAN
net0: e1000=E6:40:24:02:3D:AF,bridge=vmbr100,firewall=1
net1: e1000=2E:41:FB:9C:80:D1,bridge=vmbr100,firewall=1,tag=12
numa: 0
ostype: win10
scsihw: virtio-scsi-single
smbios1: uuid=10e81047-3e0b-43af-ae12-bcd490754eee
sockets: 1
tags: windows
virtio0: SSD-Pool01:vm-102-disk-2,discard=on,iothread=1,size=64G
vmgenid: f5e5c437-ad2e-4cd6-b5ee-bf21a2bff51b

The Issue does appear in the following VM-Config:
Code:
agent: 1
boot: order=virtio0;ide2;net0;ide0
cores: 4
ide0: none,media=cdrom
ide2: none,media=cdrom
machine: pc-i440fx-7.1
memory: 4096
meta: creation-qemu=7.1.0,ctime=1682677511
name: Win10-VLAN
net0: virtio=E6:40:24:02:3D:AF,bridge=vmbr100,firewall=1
net1: virtio=2E:41:FB:9C:80:D1,bridge=vmbr100,firewall=1,tag=12
numa: 0
ostype: win10
scsihw: virtio-scsi-single
smbios1: uuid=10e81047-3e0b-43af-ae12-bcd490754eee
sockets: 1
tags: windows
virtio0: SSD-Pool01:vm-102-disk-2,discard=on,iothread=1,size=64G
vmgenid: f5e5c437-ad2e-4cd6-b5ee-bf21a2bff51b

As you can see, the only Difference is, that I changed the Network Adapter from e1000 to VirtIO...
Here some Screenshots of the Network Traffic in the Proxmox Webgui as well:
1720002984374.png
The Traffic always drops, as soon as I change from VirtIO to e1000!


If you need any more Info from me, please tell me!

Thank you for reading.
 
Last edited:

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