config: document config options

agent/config/runtime.go

@@ -456,8 +456,21 @@ type RuntimeConfig struct {
 	AdvertiseAddrLAN *net.IPAddr
 	AdvertiseAddrWAN *net.IPAddr
 	BindAddr         *net.IPAddr
+
+	// Bootstrap is used to bring up the first Consul server, and
+	// permits that node to elect itself leader
+	//
+	// hcl: bootstrap = (true|false)
+	// flag: -bootstrap
 	Bootstrap bool
+
+	// BootstrapExpect tries to automatically bootstrap the Consul cluster,
+	// by withholding peers until enough servers join.
+	//
+	// hcl: bootstrap_expect = int
+	// flag: -bootstrap-expect=int
 	BootstrapExpect int
+
 	CAFile              string
 	CAPath              string
 	CertFile            string
@@ -467,7 +480,13 @@ type RuntimeConfig struct {
 	DNSAddrs            []net.Addr
 	DNSPort             int
 	DataDir             string
+
+	// DevMode enables a fast-path mode of operation to bring up an in-memory
+	// server with minimal configuration. Useful for developing Consul.
+	//
+	// flag: -dev
 	DevMode bool
+
 	DisableAnonymousSignature bool
 	DisableCoordinates        bool
 	DisableHostNodeID         bool
@@ -507,9 +526,21 @@ type RuntimeConfig struct {
 	RPCAdvertiseAddr      *net.TCPAddr
 	RPCBindAddr           *net.TCPAddr
 	RPCHoldTimeout        time.Duration
-	RPCMaxBurst                 int
-	RPCProtocol                 int
+
+	// RPCRateLimit and RPCMaxBurst control how frequently RPC calls are allowed
+	// to happen. In any large enough time interval, rate limiter limits the
+	// rate to RPCRate tokens per second, with a maximum burst size of
+	// RPCMaxBurst events. As a special case, if RPCRate == Inf (the infinite
+	// rate), RPCMaxBurst is ignored.
+	//
+	// See https://en.wikipedia.org/wiki/Token_bucket for more about token
+	// buckets.
+	//
+	// hcl: limit { rpc_rate = (float64|MaxFloat64) rpc_max_burst = int }
 	RPCRateLimit rate.Limit
+	RPCMaxBurst  int
+
+	RPCProtocol                 int
 	RaftProtocol                int
 	ReconnectTimeoutLAN         time.Duration
 	ReconnectTimeoutWAN         time.Duration