Security Groups Flashcards
https://docs.aws.amazon.com/vpc/latest/userguide/VPC_SecurityGroups.html
In a security group, what inbound traffic is allowed by default?
by default, all inbound traffic is blocked.
In a security group, what outbound traffic is allowed by default?
All outbound traffic is allowed
When you make a change to a security group, how long does it take for that change to take effect?
Changes to security groups take effect immediately
What is the maximum number of EC2 instances that can be associated with a single security group?
Unlimited. You can have any number of EC2 instances within a security group.
Can you have multiple security groups attached to an EC2 instance?
Yes
What does it mean that security groups are stateful?
If you create an inbound rule allowing traffic in, that traffic is automatically allowed back out again
Suppose you need to block a specific IP address from accessing your EC2 instance. How can this be accomplished using Security Groups?
You cannot block specific IP addresses using security groups
(Use network access control lists instead)
Can you specify Allow rules in a security group?
Yes
Can you specify deny rules in a security group?
NO
Can two instances within a same security group talk to each other?
only if you configure the instances to allow each other’s traffic