Network not working on VM's


New Member
Oct 18, 2023
I recently installed proxmox and I'm trying to learn, I read some topics and also the documentation but I couldn't find the solution to my problem:
I virtualized 3 servers (1 almalinux lxc, 1 windows, 1 almalinux kvm) but the network works only on the lxc server

Vm config:
root@node:~# qm config 100
agent: 1
boot: order=scsi0;ide2;net0
cores: 8
cpu: host
ide2: local:iso/AlmaLinux-8.8-x86_64-dvd.iso,media=cdrom,size=11521M
memory: 32768
meta: creation-qemu=8.0.2,ctime=1697556429
net0: virtio=86:a8:34:73:ba:0f,bridge=vmbr0
numa: 0
ostype: l26
scsi0: local-lvm:vm-100-disk-1,iothread=1,size=700G
scsihw: virtio-scsi-single
smbios1: uuid=b0314127-620a-413a-a65a-dd13b94afc80
sockets: 1
unused0: local-lvm:vm-100-disk-0
vmgenid: 9971c6cc-bc58-4786-b558-dd57f9dfbecb

/etc/network/interfaces command output from node:
root@node:~# 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

iface enp4s0 inet manual

iface enx8e04e7aa47d1 inet manual

iface enp5s0 inet manual

auto vmbr0
iface vmbr0 inet static
        address XXX.XX4.251.112/20
        gateway XXX.XX4.240.1
        bridge-ports enp4s0
        bridge-stp off
        bridge-fd 0
        post-up echo 1 > /proc/sys/net/ipv4/ip_forward
        post-up echo 1 > /proc/sys/net/ipv4/conf/enp4s0/proxy_arp
        post-up echo 1 > /proc/sys/net/ipv4/conf/vmbr0/proxy_arp

bridge fdb show command output from node (tap100 is kvm and veth101 is lxc)
root@node:~# bridge fdb show vmbr0
00:de:ad:be:ef:02 dev enp4s0 master vmbr0
9c:6b:00:26:5d:e7 dev enp4s0 master vmbr0
64:9d:99:0c:51:67 dev enp4s0 master vmbr0
00:c0:1d:c0:ff:ee dev enp4s0 master vmbr0
98:5d:82:47:d6:d9 dev enp4s0 master vmbr0
98:5d:82:47:d0:93 dev enp4s0 master vmbr0
9c:6b:00:26:37:3c dev enp4s0 vlan 1 master vmbr0 permanent
9c:6b:00:26:37:3c dev enp4s0 master vmbr0 permanent
33:33:00:00:00:01 dev enp4s0 self permanent
33:33:00:00:00:02 dev enp4s0 self permanent
01:00:5e:00:00:01 dev enp4s0 self permanent
33:33:00:00:00:01 dev enp5s0 self permanent
33:33:00:00:00:02 dev enp5s0 self permanent
33:33:00:00:00:01 dev enx8e04e7aa47d1 self permanent
33:33:00:00:00:02 dev enx8e04e7aa47d1 self permanent
33:33:00:00:00:01 dev vmbr0 self permanent
33:33:00:00:00:02 dev vmbr0 self permanent
01:00:5e:00:00:6a dev vmbr0 self permanent
33:33:00:00:00:6a dev vmbr0 self permanent
01:00:5e:00:00:01 dev vmbr0 self permanent
33:33:ff:26:37:3c dev vmbr0 self permanent
33:33:ff:00:00:00 dev vmbr0 self permanent
7e:12:aa:89:06:31 dev veth101i0 master vmbr0
fe:f1:17:da:9c:e2 dev veth101i0 vlan 1 master vmbr0 permanent
fe:f1:17:da:9c:e2 dev veth101i0 master vmbr0 permanent
33:33:00:00:00:01 dev veth101i0 self permanent
33:33:00:00:00:02 dev veth101i0 self permanent
01:00:5e:00:00:01 dev veth101i0 self permanent
86:a8:34:73:ba:0f dev tap100i0 vlan 1 master vmbr0 permanent
86:a8:34:73:ba:0f dev tap100i0 master vmbr0 permanent
33:33:00:00:00:01 dev tap100i0 self permanent
33:33:00:00:00:02 dev tap100i0 self permanent
01:00:5e:00:00:01 dev tap100i0 self permanent

ifcfg-ens18 from Vm:


ip add from Vm:


I don't know where I could be going wrong, maybe it's something small that I'm not seeing. Can you help me ?
Thank you!!


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