Hi @Sonu Singh
(Great name btw! :))
Welcome to the Hortonworks Sandbox, it is a great tool to start learning the Hortonworks platform with. I'll try to answer your questions in order.
1) I wouldn't worry too much about the splash page. If you can hit Ambari (http://127.0.0.1:8080) then you are good. The rest can be done via the web at https://hortonworks.com/tutorials/
2) on my laptop's hosts file, I have an entry as follows: 127.0.0.1 sandbox.hortonworks.com sandbox
When I need to connect to the sandbox, I just use the hostname and haven't had any issues. In fact, you should probably try ssh to your sandbox on port 2222, login as root, and change the Ambari admin password now if you haven't already done so.
ssh -p 2222 root@sandbox.hortonworks.com
(default pw is hadoop)
then as root, run: ambari-admin-password-reset
3) Most of the tutorial work on the Sandbox can be done through Ambari, so logging into Ambari and using the occasional terminal via SSH as shown above should be all you need to connect to the cluster to get started.
4) The Sandbox uses docker internally, in addition to the vmware/virtualbox layer on your machine. This can sometimes making connecting third party tools (such as Talend) to it a bit tricky because of port forwarding issues. The port not only has to be open on your virtualbox layer, but also within the Docker host internally. See this link for a good explaination and guide on opening other ports: https://hortonworks.com/tutorial/sandbox-port-forwarding-guide/section/1/
For Talend specifically, there is a good picture of how to configure the Talend side here:
https://www.talendforge.org/forum/img/members/256670/Capture-decran-2016-03-11-a-12_17_58.png
Original conversation here: https://www.talendforge.org/forum/viewtopic.php?pid=173639
