core: merge reserved_ports into host_networks

.changelog/13651.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+core: Fixed a bug where reserved ports on multiple node networks would be treated as a collision. `client.reserved.reserved_ports` is now merged into each `host_network`'s reserved ports instead of being treated as a collision.
+```

command/agent/agent.go

@@ -617,6 +617,20 @@ func convertClientConfig(agentConfig *Config) (*clientconfig.Config, error) {
 	}
 	conf.HostVolumes = hvMap
 
+	// Ensure only one of reserved.reserved_ports or
+	// host_network.reserved_ports is set.
+	/*
+		if globalRes := agentConfig.Client.Reserved.ReservedPorts; globalRes != "" {
+			for _, hostnet := range agentConfig.Client.HostNetworks {
+				if hostRes := hostnet.ReservedPorts; hostRes != "" {
+					// Global and network-specific reserved ports
+					// aren't allowed.
+					return nil, fmt.Errorf("Cannot specify reserved.reserved_ports (%q) and host_network[%q].reserved port.", globalRes, hostRes)
+				}
+			}
+		}
+	*/
+
 	// Setup the node
 	conf.Node = new(structs.Node)
 	conf.Node.Datacenter = agentConfig.Datacenter

command/agent/command.go

@@ -399,11 +399,23 @@ func (c *Command) IsValidConfig(config, cmdConfig *Config) bool {
 	}
 
 	for _, hn := range config.Client.HostNetworks {
+		if hn.ReservedPorts == "" {
+			continue
+		}
+
+		// Ensure port range is valid
 		if _, err := structs.ParsePortRanges(hn.ReservedPorts); err != nil {
 			c.Ui.Error(fmt.Sprintf("host_network[%q].reserved_ports %q invalid: %v",
 				hn.Name, hn.ReservedPorts, err))
 			return false
 		}
+
+		// Ensure ports aren't reserved multiple places. Ideally the global configuration would be the default.gT
+		/*
+			if config.Client.Reserved.ReservedPorts != "" {
+					return nil, fmt.Errorf("Cannot specify reserved.reserved_ports (%q) and host_network[%q].reserved port.", globalRes, hostRes)
+			}
+		*/
 	}
 
 	if err := config.Client.Artifact.Validate(); err != nil {

nomad/structs/funcs.go

@@ -207,8 +207,11 @@ func AllocsFit(node *Node, allocs []*Allocation, netIdx *NetworkIndex, checkDevi
 		netIdx = NewNetworkIndex()
 		defer netIdx.Release()
 
-		if collision, reason := netIdx.SetNode(node); collision {
-			return false, fmt.Sprintf("reserved node port collision: %v", reason), used, nil
+		if err := netIdx.SetNode(node); err != nil {
+			// To maintain backward compatibility with when SetNode
+			// returned collision+reason like AddAllocs, return
+			// this as a reason instead of an error.
+			return false, fmt.Sprintf("reserved node port collision: %v", err), used, nil
 		}
 		if collision, reason := netIdx.AddAllocs(allocs); collision {
 			return false, fmt.Sprintf("reserved alloc port collision: %v", reason), used, nil
@@ -530,6 +533,10 @@ func ParsePortRanges(spec string) ([]uint64, error) {
 				if err != nil {
 					return nil, err
 				}
+
+				if port > MaxValidPort {
+					return nil, fmt.Errorf("port must be < %d but found %d", MaxValidPort, port)
+				}
 				ports[port] = struct{}{}
 			}
 		case 2: