diff --git a/elk/README.md b/elk/README.md
index 6ea0608..7cae774 100644
--- a/elk/README.md
+++ b/elk/README.md
@@ -35,3 +35,26 @@ actions:
 $ pip install elasticsearch-curator
 $ curator delete-indices.yml
 ```
+
+## Send container's log to ELK
+
+```nginx
+input {
+  gelf {
+    port => 12201
+  }
+}
+```
+
+```yaml
+test:
+  image: alpine
+  command: 'sh -c "while :; do date; sleep 1; done"'
+  log_driver: gelf
+  log_opt:
+    gelf-address: udp://x.x.x.x:12201
+    tag: test
+```
+
+Search `tag: test` in kibana to show recent logging.
+
diff --git a/elk/data/pipeline/logstash.conf b/elk/data/pipeline/logstash.conf
index e5e15c4..dc8fd83 100644
--- a/elk/data/pipeline/logstash.conf
+++ b/elk/data/pipeline/logstash.conf
@@ -2,6 +2,9 @@ input {
   beats {
     port => 5044
   }
+  gelf {
+    port => 12201
+  }
 }
 
 output {
diff --git a/elk/docker-compose.yml b/elk/docker-compose.yml
index 2ce4fee..0384626 100644
--- a/elk/docker-compose.yml
+++ b/elk/docker-compose.yml
@@ -20,6 +20,7 @@ logstash:
   ports:
     - "5044:5044"
     - "9600:9600"
+    - "12201:12201/udp"
   links:
     - elasticsearch
   volumes: