build server
1. it might be good to create a test user to access github
2. no static public ip. github webhook can't be used. alternative measure is run periodic build from jenkins
3. host a private registry on build server.
4. jenkins pipeline
 - pull source code from github
 - build docker image from dockerfile
 - push the docker image to registry

5. grpc call to launch test on test server

test server
1. host test data
2. in the same local network with build server.
3. no connection to the internet
4. configure the network to allow only pulling docker images from private registry and script from build server