Information
More than one Edge server must be deployed.
GROUP ID: V-259596
RULE ID: SV-259596r961152
To ensure hostile insiders are unable to easily commit DoS attacks and reduce the effectiveness of mail flow throughout the environment, a second Edge server is deployed to allow for multiple paths of mail flow both internally and externally into the environment. This prevents a single point-of-failure and allows for service to continue in the event of a DoS attack targeting one Edge role.
Solution
At a minimum, a second server must be deployed and subscribed to.