Is it ok to deploy two or more kibana's in the same cluster? Kibana's data is stored in elasticsearch in index .kibana, so I suspect that some conflicts might happen if they are running at the same time
There's no issue with such case. The only problem might occur, when two different users are editing same object at the same time and one user will overwrite changes of the other. For multiple instances of GUI we usually use some sort of VIP (virtual IP) or sometimes we use NginX as Load Balancer and manage it with Red Hat pacemaker https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/high_availability_add-on_overview/s1-pacemakeroverview-haao
