support raising and lowering the number of running nodes

defaults/main.yml

@@ -2,6 +2,7 @@
 beacon_node_build_flavour: 'rlpx'
 beacon_node_network: 'testnet0'
 beacon_node_total_nodes: 1
+beacon_node_running_nodes: 1
 beacon_node_log_level: INFO
 
 # Image source: https://github.com/status-im/nimbus/tree/master/docker/beacon_node
@@ -12,6 +13,5 @@ beacon_node_discovery_port: 9000
 beacon_node_listening_port: 9000
 
 # general container management
-cont_state: started
 cont_recreate: false
 cont_restart: false

tasks/beacon_node.yml

@@ -12,7 +12,7 @@
     image: '{{ beacon_node_cont_image }}'
     pull: true
     restart_policy: always
-    state: '{{ cont_state }}'
+    state: '{{ "started" if is_running else "stopped" }}'
     recreate: '{{ cont_recreate }}'
     restart: '{{ cont_restart }}'
     # enable image updates via watchtower

tasks/main.yml

@@ -5,6 +5,7 @@
     public_udp_port: '{{ beacon_node_discovery_port + loop_index }}'
     container_name: 'beacon-node-{{ beacon_node_build_flavour }}-{{ beacon_node_network}}-{{loop_index }}'
     index: '{{ loop_index }}'
+    is_running: '{{ loop_index < beacon_node_running_nodes }}'
   loop: '{{ range(0, beacon_node_total_nodes) | list }}'
   loop_control:
     index_var: loop_index