Hello, Mauro, I am assuming that you are using the Practice HDPCD Exam AMI to create an EC2 instance.
What is the AMI-ID and region of the instance?
In general, lease follow these steps:
ssh to instance as the ubuntu user
after you are inside the instance, then do
ubuntu@cloud-instance:~$ sudo su -
root@cloud-instance:~# service docker status
docker start/running, process xxxx
if you do not see docker running, then
root@cloud-instance:~# service docker start
root@cloud-instance:~# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS e41b0e1dff2a hwxu/ambari_1.7.0_server_node:latest "/root/scripts/start 21 months ago Up 2 minutes 9083/tcp, 45454/tcp, 11000/tcp, 10020/tcp, 8081/tcp, 8010/tcp, 9086/tcp, 9082/tcp, 10000/tcp, 9999/tcp, 9081/tcp, 50020/tcp, 6702/tcp, 9000/tcp, 9084/tcp, 8032/tcp, 6627/tcp, 6701/tcp, 2181/tcp, 19888/tcp, 3373/tcp, 9087/tcp, 8141/tcp, 50010/tcp, 9080/tcp, 8088/tcp, 50111/tcp, 8050/tcp, 22/tcp, 9933/tcp, 8030/tcp, 6703/tcp, 3372/tcp, 9085/tcp, 8025/tcp, 50075/tcp, 6700/tcp, 50060/tcp, 50090/tcp, 0.0.0.0:8020->8020/tcp, 0.0.0.0:8080->8080/tcp, 0.0.0.0:8440->8440/tcp, 0.0.0.0:8441->8441/tcp, 0.0.0.0:50070->50070/tcp namenode
If you dont see the docker instance called "namenode" as above, then
root@cloud-instance:~# docker start namenode
give it a minute for the namenode to start then
root@cloud-instance:~# ssh namenode
once inside the namenode, restart ambari-server, ambari-agent as needed
after that go to the ambari web ui and restart all services.
Let me know if this helps
