Bastion Host and On-Premises High Availability Flashcards
Describe a good fault-tolerant way to ensure high availability for Bastion Hosts in a VPC. What is the problem with this approach?
- Keep two hosts, each in a separate availability zones
- Use a Network Load Balancer with a static IP address
- Note ALB will not work, as ALB’s operate at layer 7 and this is layer 4
- Have health checks to fail over when a host goes down
- Problem: Expensive!
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Describe a good cheap option for ensuring high availability for Bastion Hosts in a VPC. What is the problem with this approach?
- One host in one AZ, behind an ASG with health checks and a fixed EIP.
- If the host fails, the health check fails, so the ASG provisions a new EC2 instance in a separate AZ.
- You can use a user data script to provision the same EIP for the new host
- Problem: System is down while health check fails and new Bastion Host is brought up
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In the context of AWS, what does SMS stand for? (the M is not Message)
Server Migration Service
What does AWS SMS do?
Server Migration Service supports incremental replication of your on-premises servers in to AWS
(so think back-up tool, multi-site strategy, DR)
What does AWS Application Discovery Service do?
It helps enterprise customers plan migration projects by gathering information about their on-premises data centers
What does VM Import/Export do?
- Migrate existing applications in to EC2
- Can be used to export your VMs to your on-premises data center.
What are the high-level AWS services that can be used on-premises?
- Database Migration Service
- Server Migration Service
- AWS Application Discovery Service
- VM Import/Export
- Download Amazon Linux 2 as an ISO