Use config.yml consistently (not config.yaml) (#789)

README.md

@@ -93,13 +93,13 @@ Download a copy of the nebula [example configuration](https://github.com/slackhq
 
 #### 6. Copy nebula credentials, configuration, and binaries to each host
 
-For each host, copy the nebula binary to the host, along with `config.yaml` from step 5, and the files `ca.crt`, `{host}.crt`, and `{host}.key` from step 4.
+For each host, copy the nebula binary to the host, along with `config.yml` from step 5, and the files `ca.crt`, `{host}.crt`, and `{host}.key` from step 4.
 
 **DO NOT COPY `ca.key` TO INDIVIDUAL NODES.**
 
 #### 7. Run nebula on each host
 ```
-./nebula -config /path/to/config.yaml
+./nebula -config /path/to/config.yml
 ```
 
 ## Building Nebula from source

cmd/nebula-service/service.go

@@ -49,6 +49,14 @@ func (p *program) Stop(s service.Service) error {
 	return nil
 }
 
+func fileExists(filename string) bool {
+	_, err := os.Stat(filename)
+	if os.IsNotExist(err) {
+		return false
+	}
+	return true
+}
+
 func doService(configPath *string, configTest *bool, build string, serviceFlag *string) {
 	if *configPath == "" {
 		ex, err := os.Executable()
@@ -56,6 +64,9 @@ func doService(configPath *string, configTest *bool, build string, serviceFlag *
 			panic(err)
 		}
 		*configPath = filepath.Dir(ex) + "/config.yaml"
+		if !fileExists(*configPath) {
+			*configPath = filepath.Dir(ex) + "/config.yml"
+		}
 	}
 
 	svcConfig := &service.Config{