Add usage

docs/sources/getting-started.md

@@ -1,11 +1,33 @@
 # Getting Started with Pola PCE
 
-## polad 
+This page explains how to use Pola PCE.
 
-### Configuration
+## Instllation
 
-### Run Pola PCE using polad
+```bash
+$ go install github.com/nttcom/pola/cmd/polad@latest
+```
 
-## Pola PCE as a Go Native PCEP/Stateful-PCE Library
+## Configuration
 
-### Example Code
+Specify the IP address and port number for each PCEP and gRPC.
+
+```yaml
+global:
+  pcep:
+    address: "192.0.2.1"
+    port: 4189
+  grpc:
+    address: "192.0.2.1"
+    port: 50051
+```
+
+## Run Pola PCE using polad
+
+Start polad. Specify the created configuration file with the -f option.
+
+```bash
+$ polad -f polad.conf
+{"level":"info","ts":1653563205.5598016,"caller":"server/server.go:131","msg":"gRPC Listen","listenInfo":"192.0.2.1:50051","server":"grpc"}
+{"level":"info","ts":1653563205.560059,"caller":"server/server.go:99","msg":"PCE Listen","listenInfo":"192.0.2.1:4189"}
+```