我有同样的问题。事实证明，经理实例与管理者发起实例的实例具有不同的安全组。所以，我提供了完全访问这些安全组的实例。

I had the same issue. It turned out that manager instance had different Security Group than the one that was having instances launched by the manager. So, I provided full access to those security group instanced for each other.

它是固定的。