Host and vms cannot ping each other - I'm using NAT

christianinmiami

New Member
Jul 16, 2024
2
0
1
Hello,

With the help of examples on this site, I have successfully configured my proxmox hypervisor to use the wireless card and everything works -except that my virtual machines cannot ping the host, nor the host ping any of my virtual machines. I can ping the host from another machine fine and the host can ping the gateway fine. It's just the host to vm comm that's a problem.

I think it has to do with the configuration in my /etc/network/interfaces file. I am using NAT.

I did a ip neigh command and this is what I got:
(The wlp4s0 is my network card.
The 192.168.137.1 is my gateway.
The 192.168.1.200 is one of my virtual machines. Not sure why proxmox is using the wireless card to "see" it as all the wireless card is good for is to get out to the internet.)

root@pve:/etc/network# ip neigh
192.168.137.1 dev wlp4s0 lladdr 44:37:e6:89:07:85 REACHABLE
192.168.137.200 dev wlp4s0 FAILED



Would appreciate any assistance if you can.
My /etc/network/interfaces file below:

auto lo
iface lo inet loopback

auto wlp4s0
iface wlp4s0 inet static
address 192.168.137.10/24
gateway 192.168.137.1
wpa-ssid tendra
wpa-psk NONE

iface enp0s31f6 inet manual

auto vmbr0
iface vmbr0 inet static
address 192.168.137.2/24
bridge-ports none
bridge-stp off
bridge-fd 0
bridge-vlan-aware yes
bridge-vids 2-4094
post-up echo 1 > /proc/sys/net/ipv4/ip_forward
post-up iptables -t nat -A POSTROUTING -s '192.168.137.0/24' -wlp4s0 -j MASQUERADE
post-down iptables -t nat -D POSTROUTING -s '192.168.137.0/24' -wlp4s0 -j MASQUERADE
post-up iptables -t raw -I PREROUTING -i fwbr+ -j CT --zone 1
post-down iptables -t raw -D PREROUTING -i fwbr+ -j CT --zone 1
# Enable ip forwarding Route all traffic from VMs / Container through the wireless interface hiding its internal IP I needed this otherwise my packets wouldn't reach other computers/routers on my networkiface wlp4s0 inet man>

source /etc/network/interfaces.d/*



Thank you
 
Last edited:

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, and Proxmox Mail Gateway.
We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get yours easily in our online shop.

Buy now!