I am using AWS EC2 to host my internal CRM. The server has started getting spam hits and consuming quite a bit of server resource. I know that we can configure CIDRs in the security groups. When I put comma separated values and try to save it, it throws an error stating "The source needs to be a CIDR block or a Security Group ID.". Is it like I can provide only one CIDR? If yes, then how will I address this?
Each rule handles only one CIDR. You can add many rules.