HDP 2.5 Hortonworks ambari-admin-password-reset missing

So now I had the time to analyze the sandbox vm, and write it up for other users. As you stated correctly in your edit of the question, its the docker container setup of the sandbox, which confuses with two separate root users:

• via ssh [email protected] -p 2222 you get into the docker container called "sandbox". This is a CentOS release 6.8 (Final), containing all the HDP services, especially the ambari service. The configuration enforces a password change at first login for the root user. Inside this VM you can also execute the ambari-admin-password-reset and set there a password for the ambari admin.

• via console access you reach the docker host running a Centos 7.2, here you can login with the default root password for the VM as found in the HDP docs.

Coming to your sub-question with the hanging docker exec, it seems to be a bug in that specific docker version. If you google that, you will find issues discussing this or similar problems with docker. So I thought that it would be a good idea to just update the host via yum update. However this turned out to be a difficult path.

yum tried to update the kernel, but complained that there is not enough space on the boot partion.

So I moved the boot partion to the root partition:

1. edit /etc/fsab and comment out the boot entry
2. unmount /boot
3. mv /boot
4. cp -a /boot.org /boot
5. grub2-mkconfig -o /boot/grub2/grub.cfg
6. grub2-install /dev/sda
7. reboot

After that I have found out that the docker configuration is broken and docker does not start anymore. In the logs it complained about

"Error starting daemon: error initializing graphdriver: \"/var/lib/docker\" contains other graphdrivers: devicemapper; Please cleanup or explicitly choose storage driver (-s )"

So I edited /etc/systemd/system/multi-user.target.wants/docker.service and changed the ExecStart setting to:

ExecStart=/usr/bin/dockerd  --storage-driver=overlay

After a service docker start and a docker start sandbox. The container worked again and I could could login to the container and after a ambari-server restart everything worked again.

And now - with the new docker version 1.12.2, docker exec sandbox ls works again.

So to sum up the docker exec command has a bug in that specific version of the sandbox, but you should think twice if you want to upgrade your sandbox.