emqx4.3/rel/config/examples/cluster-with-etcd-ssl.conf.example

## Cluster discovery using 'etcd'
## connect to etcd over TLS

cluster {
    name = emqxcl

    ## Service discovery method for the cluster nodes
    discovery_strategy = etcd

    ## If true, the node will try to heal network partitions automatically
    autoheal = true

    etcd {
      ## List of endpoint URLs of the etcd cluster
      server = "http://ur1,http://ur2"

      ## Key prefix used for EMQX service discovery
      prefix = emqxcl

      ## Expiration time of the etcd key associated with the node.
      node_ttl = 1m

      ssl_options {
          ## Trusted PEM format CA certificates bundle file
          cacertfile = "${EMQX_ETC_DIR}/certs/etcd-cacert.pem"

          ## PEM format certificates chain file
          certfile = "${EMQX_ETC_DIR}/certs/etcd-client-cert.pem"

          ## PEM format private key file
          keyfile = "${EMQX_ETC_DIR}/certs/etcd-client-key.pem"

          ## Enable or disable peer verification
          verify = verify_none ## use verify_peer to enable
      }
    }
}