PBS as KVM VM using bridge network on Ubuntu host.

[pve_noobie]

I am trying to setup Proxmox Backup Server as a KVM VM that uses a bridge network on a Ubuntu host. My required setup is as follows

- Proxmox VE setup on a dedicated host on my homelab - done
- Proxmox Backup Server setup as a KVM VM on Ubuntu desktop
- Backup VMs from Proxmox VE to PBS across the network
- Pass through a physical HDD for PBS to store backups
- Network Bridge the PBS VM to the physical homelab (recommended by someone for performance)


Before I started my Ubuntu host simply had a static IP address. I have followed this guide (https://www.dzombak.com/blog/2024/02/Setting-up-KVM-virtual-machines-using-a-bridged-network.html) to setup a bridge and this appears to be working. My Ubuntu host is now receiving an IP address via DHCP as below (would prefer a static Ip for the Ubuntu host but hey ho)



: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host noprefixroute
valid_lft forever preferred_lft forever
2: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel master br0 state UP group default qlen 1000
link/ether xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
altname enp0s31f6
3: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
inet 192.168.1.151/24 brd 192.168.1.255 scope global dynamic noprefixroute br0
valid_lft 85186sec preferred_lft 85186sec
inet6 xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx/64 scope global temporary dynamic
valid_lft 280sec preferred_lft 100sec
inet6 xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx/64 scope global dynamic mngtmpaddr
valid_lft 280sec preferred_lft 100sec
inet6 fe80::78a5:fbff:fe79:4ea5/64 scope link
valid_lft forever preferred_lft forever
4: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
link/ether xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
valid_lft forever preferred_lft forever


However, when I create the PBS VM the only option I have for management network interface is enp1s0 - xx:xx:xx:xx:xx (virtio_net) which then allocates me IP address 192.168.100.2 - it doesn't appear to be using the br0 and giving me an IP in range 192.168.1.x


Here are the steps I have followed:

1. edit file in /etc/netplan to below

network:
version: 2
ethernets:
eno1:
dhcp4: true
bridges:
br0:
dhcp4: yes
interfaces:
- eno1

This appears to be working as eno1 not longer has static IP and there is a br0 now listed (see ip add above)

2. sudo netplan try - didn't give me any errors

3. created file called called kvm-hostbridge.xml

<network>
<name>hostbridge</name>
<forward mode="bridge"/>
<bridge name="br0"/>
</network>

4. Create and enable this network

virsh net-define /path/to/my/kvm-hostbridge.xml
virsh net-start hostbridge
virsh net-autostart hostbridge

5. created a VM that passes the hostbridge t virt-install



virt-install \
--name pbs \
--description "Proxmox Backup Server" \
--memory 4096 \
--vcpus 4 \
--disk path=/mypath/Documents/VMs/pbs.qcow2,size=32 \
--cdrom /mypath/Downloads/proxmox-backup-server_3.2-1.iso \
--graphics vnc \
--os-variant linux2022 \
--virt-type kvm \
--autostart \
--network network=hostbridge



VM is created with 192.168.100.2 so doesn't appear to be using the network bridge

Any ideas on how to get VM to use a network bridge so it has direct access to the homelab network