[Rspamd-Users] Unable to See Neighbours using a Load Balancer

[Alexander Moisseev]

On 25.10.2025 0:37, Kendall Marino via Users wrote:
> Each separate instance runs both rspamd and nginx, and I am able to query
> the /neighbours endpoint on one instance successfully from another.
> However, external traffic to each instance is directed solely by a load
> balancer so when the browser attempts to query the /stat endpoint for each
> neighbour it fails and the UI displays the errors below repeatedly.
> 
> "Cannot get server status"
> "request failed"
> 
> These two instances are set up identically. The documentation doesn't seem
> to note a way for the instances to interact directly; what is the solution
> to resolve this setup with a load balancer so the instances are visible to
> each other?
> 

Hi Kendall,

There’s no way to make the Rspamd UI aggregate stats purely through the load balancer, since it’s the browser that queries each backend.

The WebUI retrieves statistics for each neighbour directly from the browser, not via the backend. This means the browser must be able to reach each neighbour’s /stat endpoint at the address configured under neighbours { ... }.

In your setup, the load balancer hides the real backend addresses, so the browser’s requests to those neighbour URLs fail. The /neighbours endpoint works from the command line because Rspamd itself can reach the internal addresses, but the browser cannot.

To fix this, you need to expose each instance directly to the browser — ensure the neighbour hostnames or IPs in your options.inc are reachable from the client viewing the WebUI (for example, by using DNS names that resolve to each instance instead of the load balancer).

Best,
Alexander