Support old recursor config for backwards compatibility

command/agent/config.go

@@ -97,6 +97,11 @@ type Config struct {
 	// DataDir is the directory to store our state in
 	DataDir string `mapstructure:"data_dir"`
 
+	// DNSRecursors can be set to allow the DNS servers to recursively
+	// resolve non-consul domains. It is deprecated, and merges into the
+	// recursors array.
+	DNSRecursor string `mapstructure:"recursor"`
+
 	// DNSRecursors can be set to allow the DNS servers to recursively
 	// resolve non-consul domains
 	DNSRecursors []string `mapstructure:"recursors"`
@@ -500,6 +505,11 @@ func DecodeConfig(r io.Reader) (*Config, error) {
 		result.RetryInterval = dur
 	}
 
+	// Merge the single recursor
+	if result.DNSRecursor != "" {
+		result.DNSRecursors = append(result.DNSRecursors, result.DNSRecursor)
+	}
+
 	return &result, nil
 }
 

command/agent/config_test.go

@@ -109,7 +109,7 @@ func TestDecodeConfig(t *testing.T) {
 	}
 
 	// DNS setup
-	input = `{"ports": {"dns": 8500}, "recursor": ["8.8.8.8","8.8.4.4"], "domain": "foobar"}`
+	input = `{"ports": {"dns": 8500}, "recursors": ["8.8.8.8","8.8.4.4"], "recursor":"127.0.0.1", "domain": "foobar"}`
 	config, err = DecodeConfig(bytes.NewReader([]byte(input)))
 	if err != nil {
 		t.Fatalf("err: %s", err)
@@ -119,7 +119,7 @@ func TestDecodeConfig(t *testing.T) {
 		t.Fatalf("bad: %#v", config)
 	}
 
-	if len(config.DNSRecursors) != 2 {
+	if len(config.DNSRecursors) != 3 {
 		t.Fatalf("bad: %#v", config)
 	}
 	if config.DNSRecursors[0] != "8.8.8.8" {
@@ -128,6 +128,9 @@ func TestDecodeConfig(t *testing.T) {
 	if config.DNSRecursors[1] != "8.8.4.4" {
 		t.Fatalf("bad: %#v", config)
 	}
+	if config.DNSRecursors[2] != "127.0.0.1" {
+		t.Fatalf("bad: %#v", config)
+	}
 
 	if config.Domain != "foobar" {
 		t.Fatalf("bad: %#v", config)

website/source/docs/agent/http.html.markdown

@@ -333,6 +333,7 @@ It returns a JSON body like this:
     "Server": true,
     "Datacenter": "dc1",
     "DataDir": "/tmp/consul",
+    "DNSRecursor": "",
     "DNSRecursors": [],
     "Domain": "consul.",
     "LogLevel": "INFO",

website/source/docs/agent/options.html.markdown

@@ -321,6 +321,9 @@ definitions support being updated during a reload.
 
 * `protocol` - Equivalent to the `-protocol` command-line flag.
 
+* `recursor` - Provides a single recursor address. This has been deprecated, and
+  the value is appended to the `recursors` list for backwards compatibility.
+
 * `recursors` - This flag provides addresses of upstream DNS servers that are used to
   recursively resolve queries if they are not inside the service domain for consul. For example,
   a node can use Consul directly as a DNS server, and if the record is outside of the "consul." domain,