SDN - Trying to make VMs on different hosts talk to each other

[dpearceFL]

I have a three-node Proxmox cluster, all running 8.2.7. I would like to create two Linux VMs on different nodes in the same cluster and have them be able to talk to each other. I assume using the SDN functionality is the proper way to do this.

1. I have created a zone with an ID of sdn100
2. I have created a VNet using sdn100
3. I then created a subnet off of that VNet using 10.2.0.0/24 and a gateway of 10.2.0.1 and a DHCP range of 10.2.0.10 to 10.2.0.250

The two VMs will request and are granted IP addresses with that range.

When I log into the two VMs, they can not ping the other VM.

What am I missing? Thanks!

 

[em3034]

Did you create a simple zone?
This type does not allow communication between nodes.
See https://pve.proxmox.com/pve-docs/chapter-pvesdn.html#pvesdn_zone_plugin_simple

 

[dpearceFL]

You are right, I was using "simple".

I deleted the entries in Proxmox associated with my simple zone.

I have tried "VLAN Zones" but DHCP is no longer working.

Now what?

 

[em3034]

Correct, DHCP is only working for simple as far as I know, it will be there in the future for other zone types.

What is your goal? To test SDN or to make a VM running on different nodes?

If your goal is to have VMs communicating between eachother then you don't need SDN, you just need to configure your Proxmox nodes to access your home subnets, and all VMs should be able to talk to all others (as long as routing and firewall allows for it).

But it depends on your router. I have a pfSense as main router and I can create VLANs with DHCP enabled.

But you could also install a pfSense router as a Virtual machine, configure it to provide VLANs/DHCP and point your VMs to this router.
Many options are available.

 

[dpearceFL]

What is your goal? To test SDN or to make a VM running on different nodes?

A bit of both. I'm exploring what SDN is good for.

But it depends on your router.

While I never said this, I am doing this in a corporate environment. I have three Proxmox 8.2 nodes. I am using two NICs. One NIC goes to our general network. The other NIC on all three nodes is plugged into a standalone switch. The latter network is used for all of the VMs. I was hoping to replace the network switch with SDN. I guess I will have to stand up something like dnsmasq in a VM.

Given this information, which SDN option should I use?

Thanks.