SDN with Cluster and several services

[Bohem]

Hello Proxmox Community,

I'm a long-time lurker, and today I'm the one posting

I'm trying to set up an SDN (Software-Defined Networking) on a cluster of 2 Proxmox servers to create a high-availability (HA) datastore using OpenMediaVault (OMV) and DRBD (one OMV instance on each Proxmox server, with a master/slave relationship, VIP, and iSCSI link). To achieve this, they need to be on the same network. I understand I can achieve this with OVH vRack, but I'm exploring other possibilities.

So far, I've successfully pinged between my two OMV instances across both Proxmox servers in the same LAN using VXLAN:

192.168.1.1 (OMV1) <-> Proxmox1 <----VNet----> Proxmox2 <-> 192.168.1.2 (OMV2) = PING IS OK

However, my main issue is that I cannot get several services (such as SSH or HTTP) to work.

From a management VM (192.168.1.10) on Proxmox1, I can access OMV1 via web or SSH at 192.168.1.1, but when I try to access OMV2 via web or SSH, I cannot, despite successful pinging.

I've also tried:

• Creating a subnet linked to my VNet, but I cannot ping anything with that setup.
• Creating a simple SDN with a subnet and DHCP, but I cannot get ping responses (and my VM doesn't receive any DHCP lease).

What do I need to make my setup work properly with all protocols?

I would love to get this working so that I can extend SDN to my production cluster for various use cases (such as pfSense HA and one management VM for all VMs across the cluster).

Thanks in advance.
(If anyone can assist and prefers to communicate in French, I would appreciate responses in French.)

 

[spirit]

http or https ?

if it's only ssh/https or other ssl protocol, it could be a mtu problem with fragmentation. (try mtu 1400 in your vm nic config for example)

 

[Bohem]

Hello,
Thank you for the quick response!
I have set the MTU to 1400 on my OMV2, and I can now access the WebUI (HTTP).
Should I also set the MTU to 1400 on all my VM NICs to prevent future issues?

 

[spirit]

Hello,
Thank you for the quick response!
I have set the MTU to 1400 on my OMV2, and I can now access the WebUI (HTTP).
Should I also set the MTU to 1400 on all my VM NICs to prevent future issues?

yes. (1450 should be enough with vxlan.)


another way : you need to increase your physical network and hypervisor nics with minimum 1550 mtu.


vxlan need 50 more bytes for tunneling