docker/README.md: CLI: how to register new domain
Specify "host" as the network when start Cadence-ClI with docker.
`docker run --network=host --rm ubercadence/cli:master`
@@ -14,7 +14,10 @@ docker-compose up
View metrics at localhost:8080/dashboard
View Cadence-Web at localhost:8088
-Use Cadence-CLI with `docker run --rm ubercadence/cli:master`
+Use Cadence-CLI with `docker run --network=host --rm ubercadence/cli:master`
+
+For example to register new domain 'test-domain' with 1 retention day
+`docker run --network=host --rm ubercadence/cli:master --do test-domain domain register -rd 1`
Using a pre-built image
