[SOLVED] Network configuration Windows Server 2019

[showiproute]

Hello everyone,

I am having an "interessting" issue:
I migrated from virtual Sophos XG to virtual OPNsense.

Now my Window Server 2019 thinks I have attached an 100Gbit link (which is a 1Gbit in real) and does no longer connect.
The simple command

ipconfig

also shows me just the configured IP address without subnet mask or gateway which usually should be included.

My steps to troubleshoot so far:
Reconfigured NIC with Intel E1000 -> did not solve it
Reset TCP/IP stack within Windows -> same


Any ideas what is going on?!

 

[showiproute]

It seems that the MAC address is not being forwarded correctly from Proxmox to the network.
The virtual MAC is being used by Windows Server but it mentions a conflict as there is already an existing one and also on the router I can see that there is a different one.

 

[aaron]

Can you please show the VMs config (qm config <vmid>) and the /etc/network/interfaces config of the node?

 

[showiproute]

Hi @aaron

my VM config would bie:

root@kvm:~# qm config 110
agent: 1
boot: order=scsi0
cores: 4
ide2: local:iso/virtio-win-0.1.185.iso,media=cdrom,size=402812K
memory: 2048
name: WindowsServerDC2
net0: virtio=02:9D:2A:EE:F4:01,bridge=vmbr0
numa: 1
onboot: 1
ostype: win10
scsi0: local-lvm:vm-110-disk-0,size=70G
scsihw: virtio-scsi-pci
smbios1: uuid=2de8bc69-9255-4b8b-a3d4-cc467718e4f1
sockets: 1
startup: order=2
vga: qxl
vmgenid: fabb34ae-bad2-4eeb-be3a-926598f9e6de

and network config would be:

# 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

iface enp2s0 inet manual

iface enp4s0 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.101.251/24
        gateway 192.168.101.254
        bridge-ports enp2s0
        bridge-stp off
        bridge-fd 0
        bridge-vlan-aware yes
        bridge-vids 2-4094

auto vmbr1
iface vmbr1 inet dhcp
        bridge-ports enp4s0
        bridge-stp off
        bridge-fd 0

 

[showiproute]

I am not sure why this occurs but within Windows' event log I receive a "Tcpip" error mentioning that my IP (I am using a static one) is already linked to a MAC address.

Strange thing: I am unable to find this MAC address somewhere?!

 

[showiproute]

Okay I solved it: It was a "misconfigured" legacy Cisco router which took over nearly any IP address of my local range....

 

[aaron]

Good to hear that you were able to solve it and thank you for posting the cause of the problem. Would you be so kind to mark the thread as solved? To do so, edit the first post and select the prefix from the dropdown next to the title. Thanks

 

[showiproute]

Sure!