Finally I solved my problem. It is because of GFW (great firewall) between mainland and the rest of the world. The doc here is very good one if one doees not have firewall.

With firewall, one needs to do following two things:

1. download image from mirror site:

docker pull daocloud.io/daocloud/google_containers_pause-amd64:3.0

2. Tag it

docker tag daocloud.io/daocloud/google_containers_pause-amd64:3.0 gcr.io/google_containers/pause-amd64:3.0

So far, I still could not run dashboard. But same logic, I need to download image …