[SOLVED] SDN VLAN: cannot ping between VM on different nodes

[Bruno T.]

Hi,

I'm currently testing SDN with 7.4. I configure a VLAN zone as per https://pve.proxmox.com/pve-docs-7/chapter-pvesdn.html and https://pve.proxmox.com/wiki/Software-Defined_Network#pvesdn_setup_examples.

This is a very basic setup with a Zone "cluster1" (no DNS, no DHCP for now) and a VNet "clus1vn" with tag 10.
Two nodes are in the zone: pvelab4 and pvelab5.

There is one VM per node. The VM cannot ping each other. This might be a very stupid misconfiguration but I'm struggling to find the root cause, thus any help would be greatly appreciated.

When I migrate one of the VM to the same node than the other, the ping works.

root@pvelab5:~# cat /etc/network/interfaces.d/sdn
#version:5

auto clus1vn
iface clus1vn
    bridge_ports ln_clus1vn
    bridge_stp off
    bridge_fd 0
    alias cluster1 VNet

auto ln_clus1vn
iface ln_clus1vn
    link-type veth
    veth-peer-name pr_clus1vn

auto pr_clus1vn
iface pr_clus1vn
    link-type veth
    veth-peer-name ln_clus1vn

auto vmbr0v10
iface vmbr0v10
    bridge_ports  eno1.10 pr_clus1vn
    bridge_stp off
    bridge_fd 0

(same conf on pvelab4).

Then I reconfigured 2 test VMs to use the new VNet instead of vmbr0.

root@pvelab4:~# qm config 1014 | grep ^net0
net0: virtio=42:50:54:10:14:00,bridge=clus1vn

root@pvelab5:~# qm config 1015 | grep ^net0
net0: virtio=42:50:54:10:15:00,bridge=clus1vn

The network configuration of each pve node is:

root@pvelab4:~# cat /etc/network/interfaces
# network interface settings; autogenerated
# [...]

auto lo
iface lo inet loopback

auto eno1
iface eno1 inet manual

iface eno2 inet manual

auto vmbr0
iface vmbr0 inet static
    address 172.31.0.14/22
    gateway 172.31.0.1
    bridge-ports eno1
    bridge-stp off
    bridge-fd 0

source /etc/network/interfaces.d/*

root@pvelab5:~# cat /etc/network/interfaces
# network interface settings; autogenerated
# [...]

auto lo
iface lo inet loopback

auto eno1
iface eno1 inet manual

iface eno2 inet manual

auto vmbr0
iface vmbr0 inet static
    address 172.31.0.15/22
    gateway 172.31.0.1
    bridge-ports eno1
    bridge-stp off
    bridge-fd 0

source /etc/network/interfaces.d/*

 

[spirit]

config looks fine.
do you allow vlan 10 on your physical switch port ?

(BTW, sdn is really only supported on pve8, no bugfix will be done on pve7.X)

 

[Bruno T.]

Merci @spirit !
Indeed that was a stupid misconfiguration, the ports were untagged in the physical switch... Once tagged, it works perfectly fine!

We definitely plan to upgrade to 8.1. but I was very curious about SDN after reading the 8.1 PR.