Update README.md

6/6.1/ui/README.md

+# Apache SkyWalking UI Docker Files
+
+<img src="http://skywalking.apache.org/assets/logo.svg" alt="Sky Walking logo" height="90px" align="right" />
+
+**SkyWalking**: an APM(application performance monitor) system, especially designed for 
+microservices, cloud native and container-based (Docker, Kubernetes, Mesos) architectures.
+
+# How to use this image
+
+## Start a container to connect oap server whose address is `oap:12800`
+
+```
+$ docker run --name oap --restart always -d -e SW_OAP_ADDRESS=oap:12800 apache/skywalking-ui:6.1.0
+```
+
+# Configuration
+
+We could set up environment variables to configure this image.
+
+## SW_OAP_ADDRESS
+The address of OAP server. Default value is `127.0.0.1:12800`.
+ 
+## SW_TIMEOUT
+Reading timeout. Default value is `20000`(millisecond).
+
+# License
+[Apache 2.0 License.](/LICENSE)