SSM Deep Dive·0/54 min
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🗂️SSM Overview·5 min readModule 1 of 9
SSM Overview
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AWS Systems Manager
Patch, configure, automate, and connect to your entire fleet — no SSH keys, no bastion hosts, full audit trail.
~54 min total9 modules9 quiz questionsDOP-C02 High priority
AWS Systems Manager (SSM) is the central management plane for EC2 and on-premises servers. It replaces SSH-based management with secure, auditable, agent-based operations. The SSM Agent runs on the instance; all communication is outbound HTTPS to SSM endpoints — no inbound ports or bastion hosts required.
Prerequisites — The Managed Instance Holy Trinity
1
SSM Agent
Pre-installed on Amazon Linux 2/2023, Windows, Ubuntu 20+. Must be running.
2
IAM Role
AmazonSSMManagedInstanceCore policy attached to instance profile.
3
Network
Outbound HTTPS to SSM endpoints. Via public internet OR VPC endpoints (com.amazonaws.region.ssm, ssmmessages, ec2messages).
SSM Capabilities — Click Each
🎯Instance not appearing in Fleet Manager? Check all three prerequisites: (1) SSM Agent running, (2) IAM role with AmazonSSMManagedInstanceCore, (3) network connectivity to SSM endpoints. For private subnet instances, you need VPC endpoints OR a NAT Gateway — SSM traffic cannot use an Internet Gateway directly.