Please don't respond with additional questions as "answers". Comment on only the original post or answer.
Are you using a Elastic Load Balancer (ELB) ?
I am not an expert, but this is what I think:
I don't think that I need ELB , because I don't need to load balancing between several instances.. I only have one, as you could see
What do you think?
I'm able to connect to this IP via SSH.
make sure you're using strong splunk password. You can change it via SSH with
su - splunk
splunk edit user
check AWS security group -> inbound rules that 8000/TCP is allowed
check iptables with iptables-save that 8000/TCP is allowed
FYI: t2.micro is too small für Splunk
Let me know how it went