Adding a New Node on My Local Network to an Existing Proxmox Cluster - Need Some Help with Configuration

ale.ttone

New Member
Sep 12, 2023
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Hello Proxmox community,

I'm having a bit of trouble adding a new node from my local network to my existing Proxmox cluster, which is currently working well with three nodes hosted on different VDS instances from OVH.
When I try to add the new node, it shows up in the cluster, but it's marked as disconnected, and I keep getting this error message:

"hostname lookup 'test' failed - failed to get address info for: test: No address associated with hostname (500)"

I understand that there may be some extra configuration needed to make a local LAN node visible from the outside, like maybe opening up some ports on my router or messing with host settings.
The problem is, I'm not exactly sure what needs to be done.
Any tips or advice on how to get this sorted out and add my new node to the Proxmox cluster would be greatly appreciated.

Thanks a lot in advance for your help!

Alessandro
 
I'm having a bit of trouble adding a new node from my local network to my existing Proxmox cluster, which is currently working well with three nodes hosted on different VDS instances from OVH.
Thats something you usually want to avoid. Corosync needs low latency and over the internet its probably more than the 10ms you should be below.
 
Hi Dunuin,

I currently have two OVH servers in Canada and one in France.
The latency between Canada and France is approximately 100ms, and I haven't encountered any issues.
The cluster is primarily used for monitoring the online status of all the nodes and VMs, and I'm not utilizing any backup/restore functions.
Do you have any suggestions on how I can make them communicate? I'd like to give it a shot and see if it works.

Thanks!
 
https://pve.proxmox.com/wiki/Cluster_Manager#pvecm_cluster_network_requirements said:
Network Requirements
The Proxmox VE cluster stack requires a reliable network with latencies under 5 milliseconds (LAN performance) between all nodes to operate stably. While on setups with a small node count a network with higher latencies may work, this is not guaranteed and gets rather unlikely with more than three nodes and latencies above around 10 ms.
The network should not be used heavily by other members, as while corosync does not uses much bandwidth it is sensitive to latency jitters; ideally corosync runs on its own physically separated network. Especially do not use a shared network for corosync and storage (except as a potential low-priority fallback in a redundant configuration).
Before setting up a cluster, it is good practice to check if the network is fit for that purpose. To ensure that the nodes can connect to each other on the cluster network, you can test the connectivity between them with the ping tool.
If the Proxmox VE firewall is enabled, ACCEPT rules for corosync will automatically be generated - no manual action is required.
 
I get it.
My intention was simply to experiment with configuring the nodes and the cluster in a way that allows them to communicate effectively.
If this approach doesn't prove to be reliable, I won't integrate the node into my local network.

If I'm understanding this correctly, all I'd need to do is ensure that I can ping between the two nodes.
After that, I would just have to open these ports on my router and set up port forwarding to redirect external IP traffic to the local IP.

Would this be enough?

Ports used by Proxmox VE​

  • Web interface: 8006 (TCP, HTTP/1.1 over TLS)
  • VNC Web console: 5900-5999 (TCP, WebSocket)
  • SPICE proxy: 3128 (TCP)
  • sshd (used for cluster actions): 22 (TCP)
  • rpcbind: 111 (UDP)
  • sendmail: 25 (TCP, outgoing)
  • corosync cluster traffic: 5405-5412 UDP
  • live migration (VM memory and local-disk data): 60000-60050 (TCP)

Thanks
 

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