How to build the instance.
First of all, You should set some network configuration
1: Create a Network,
2: create a Security group,
Open the port as below:
22 53 80 389 8080 34386 443 so on as your real requirement.
3: create Router
4: apply network to the router
Launch the instance
Instance Name is SalesForce-Centos7.4-without-SElinux
Source Flavor Network Security Group Key Pair need to be set, please see below screenshot.
Others can keep default.
You will get below pop-up box
Fill the Instance name: SalesForce-Centos7.4-without-SElinux
Wait 1 or 2 minutes, you can see your instance in the instance list page.
The last step is fix one IP to your instance. as picture below: