Windows 10 guest and bridged interface

[nickq]

Hello everyone!
This is my first post on the Proxmox community forum!

I'm testing Proxmox VE on my personal lab and I'm facing a problem with a Windows 10 64bit guest with bridged configuration.
Trying to be more specific... ;-)

The problem
Microsoft Windows 10 client with bridged network (on Proxmox VE 5.0-32) cause the router (OpenWRT Chaos Calmer on a Linksys E2000) to crash and reboot. The issue is independant about the virtual adapter used: it occurs both with VirtIO and Intel E1000. No problems at all if I use the NAT configuration.
The issue doesn't occour with the same VM on another server, where KVM runs on Ubuntu (Xenial Xerus 16.04.1 LTS amd64).
Both servers are connected to the router via a Layer 2 switch.
For my virtual environment I use 2 different VLANs (Application and DMZ) which share the same NIC on the server and on the router.

Here are some differences of the configuration between the servers.

1. NIC
Proxmox:

Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8169 PCI Gigabit Ethernet Controller (rev 10)​

Ubuntu:

Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06)​

2. Kernel
Proxmox:

4.10.17-3-pve #1 SMP PVE 4.10.17-23 x86_64 GNU/Linux​

Ubuntu:

4.4.0-96-generic #119-Ubuntu SMP x86_64 GNU/Linux​

3. Network config
Proxmox:

# VLAN 2 "Lab-Appl"
iface enp4s5.2 inet manual
    vlan-raw-device enp4s5

 # VLAN 3 "Lab-DMZ"
iface enp4s5.3 inet manual
    vlan-raw-device enp4s5

auto vmbr0
iface vmbr0 inet static
    address 192.168.2.14
    netmask 255.255.255.0
    bridge_ports enp4s5.2
    bridge_stp off
    bridge_fd 0

auto vmbr1
iface vmbr1 inet static
    address 192.168.3.14
    netmask 255.255.255.0
    bridge_ports enp4s5.3
    bridge_stp off
    bridge_fd 0

Ubuntu:

# VLAN 2 "Lab-Appl"
auto enp4s0.2
iface enp4s0.2 inet static
    address 192.168.2.13
    netmask 255.255.255.0
    vlan-raw-device enp4s0

# VLAN 113 "Lab-DMZ"
auto enp4s0.3
iface enp4s0.3 inet static
    address 192.168.3.13
    netmask 255.255.255.0
    vlan-raw-device enp4s0

On the virt-manager GUI, I set in the VM NIC configuration:

Network source: Host device enp4s0.2: macvtap

Source mode: Bridge​

4. Some packages version
Proxmox:

pve-qemu-kvm    2.9.1-1    amd64    Full virtualization on x86 hardware
bridge-utils    1.5-13+deb9u1    amd64    Utilities for configuring the Linux Ethernet bridge

Ubuntu:

qemu-kvm    1:2.5+dfsg-5ubuntu10.16    amd64    QEMU Full virtualization
bridge-utils    1.5-9ubuntu1    amd64    Utilities for configuring the Linux Ethernet bridge

5. Extract of the VM configuration file
Proxmox:

net0: virtio=TH:EM:AC:AD:RE:SS

Ubuntu:

<interface type='direct'>
  <mac address='TH:EM:AC:AD:RE:SS'/>
  <source dev='enp4s0.2' mode='bridge'/>
  <model type='virtio'/>
  <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</interface>

...obiously I masked the mac-addresses, as well as the IP address and the VLANs IDs.

Conclusion
I understand that Proxmox and KVM on Ubuntu are substantially different systems. ...I'm just hoping that the informations provided could help!
Let me know if you need more informations... and thanks to whom will read and answer!

 

[Alwin]

What network traffic are the VMs producing, when the router reboot. A quick guess, Windows might run its neighborhood discovery.

 

[nickq]

Hi Alwin!
I was considering to connect one linux vm (or a raspberry) to the same VLAN with the same address configured on the router interface ...obiously after have the OpenWRT disconncterd!
Running tcpdump on the machine with the router IP I should be able to find possible anomalies about the traffic.
Btw, I find strange the same issue doesn't occour with Ubuntu+libvirt... :-/
Thanks for your suggestion!

 

[Alwin]

You could do a tcpdump on the bridge interface to see what might be going on. You have different versions on Ubuntu and Proxmox, so many possibilities.

 

[nickq]

Hello!
Done the tcpdump (on the bridge interface), but the issue seems gone for now! :-/

I tried to enable/disable/enable again windows network discovery, surf the internet, check for updates, connect via rdp... not a problem anymore.

I can't figure out what caused the original issue, so I don't know if I must be happy or not ...till it will happen again! In that case I'll update this thread.

Thanks a lot for now.
Bye.

-
Edit: the issue happened again when I just stopped to look for it! :-/
Still analyzing...