Nomad

qumo has no runtime peer-discovery service — relays connect to a fixed, comma-separated list of addresses configured via PEERS (see Configuration → Static peers). Running on Nomad is no different: point each relay’s PEERS at a stable address for the peer(s) it should connect to.

How it works

Each relay is a normal Nomad task; no service discovery lookups happen at the relay’s own initiative.
To give a relay a stable address other relays can dial (e.g. a hub other edges connect to), give its Nomad job a fixed, well-known address — a static host port, a Consul DNS name (e.g. role-hub.qumo-relay.service.consul:4433 when running Consul alongside Nomad), or a Docker network alias if relays share a Docker network (see the demo below).
Edges set PEERS to their hub’s address(es). Hubs leave it unset unless they too connect upward (e.g. a further regional hub).
Every relay that peers needs a peer identity: the relay CA’s certificate and a peer certificate of its own, as files in the task (CA_FILE, PEER_CERT_FILE, PEER_KEY_FILE). That includes a hub that dials no one, since it is dialed. A relay with PEERS and no identity refuses to start. See TLS & mTLS for what the certificate must contain.

Configuration

Variable	Default	Description
`PEERS`	(empty)	Comma-separated relays to dial, e.g. an edge’s hub(s); each host is resolved to all its addresses. Needs the three settings below.
`CA_FILE`	(empty)	The relay CA’s certificate (PEM), a path relative to the task’s working directory.
`PEER_CERT_FILE` / `PEER_KEY_FILE`	(empty)	This relay’s own peer certificate and key, issued by that CA. One per relay: render them per allocation, never one pair for the whole job.

--role hub/--role edge is a CLI flag on qumo relay — it is an operator-facing label logged at startup for visibility only and does not affect which addresses are dialed. See CLI → relay.

Demo job spec

docker/nomad/qumo-cluster.nomad.hcl runs a real single-region Nomad cluster exercising this topology: 2 hubs, each given a stable Docker-network alias via the docker driver’s network_aliases config, and 2 edges with a fixed PEERS = "hub-0:4433,hub-1:4433". See docker/nomad/README.md for how to run and verify it.

# hub task
config {
  network_mode    = "qumo-net"
  network_aliases = ["hub-${NOMAD_ALLOC_INDEX}"]
  args            = ["relay", "--role", "hub"]
}

# edge task
env {
  PEERS          = "hub-0:4433,hub-1:4433"
  CA_FILE        = "certs/peer-ca.crt"
  PEER_CERT_FILE = "certs/peers/edge-asia-${NOMAD_ALLOC_INDEX}.crt"
  PEER_KEY_FILE  = "certs/peers/edge-asia-${NOMAD_ALLOC_INDEX}.key"
}

The hub task sets the same three peer settings with its own files, and no PEERS.

For a production Nomad deployment with Consul installed, a Consul DNS name (<service>.service.consul) is usually the simpler stable address to put in PEERS instead of a fixed per-index alias.

Verify

nomad service info qumo-relay

On an edge, qumo_relay_peers_connected (from /metrics) should reach the number of addresses in its PEERS; on a hub with no PEERS set, it stays 0.

Peer topology TLS & mTLS