SecurityGroup

• only allow rules
• refrence ip or other sg
• essential a firewall
• access to ports
• autherized ip ranges
• inbound and outbound
• one group to many instances
• vpc and region bound
• is not on the ec2 but before
• use seperate sg for ssh access
• time out usually means sg issue
• connection refused application or server error
• default all inbound is blocked all outbound allowed
• stateful, if traffic is allowed out its allowed back in