reboot-instance.sh

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Purpose

Reboot running EC2 instances and optionally wait until system and instance checks return ok.

Location

cloud/aws/ec2/reboot-instance.sh

Preconditions

  • Required tools: bash, aws, date, sleep
  • Required permissions: ec2:DescribeInstances, ec2:DescribeInstanceStatus, ec2:RebootInstances
  • Required environment variables: none

Arguments

Flag Required Default Description
--id INSTANCE_ID Cond. none Instance ID (repeatable)
--ids CSV Cond. none Comma-separated instance IDs
--region REGION No AWS CLI default AWS region override
--profile PROFILE No AWS CLI default AWS profile override
--wait No true Wait for status checks to pass
--no-wait No false Return immediately after reboot API call
--timeout SEC No 1200 Wait timeout
--poll-interval SEC No 15 Poll interval during wait
--dry-run No false Print commands only

Scenarios

  • Happy path: running instance reboots and health checks recover to ok.
  • Common operational path: service-level remediation before deeper repair actions.
  • Failure path: target instance not in running state or status checks stay degraded.
  • Recovery/rollback path: escalate to stop/start or replacement if reboot does not recover health.

Usage

cloud/aws/ec2/reboot-instance.sh --id i-0123456789abcdef0
cloud/aws/ec2/reboot-instance.sh --ids i-0123456789abcdef0,i-0fedcba9876543210 --no-wait
cloud/aws/ec2/reboot-instance.sh --id i-0123456789abcdef0 --timeout 1800 --poll-interval 20

Behavior

  • Main execution flow:
  • validates running-state precondition for each target
  • issues reboot request
  • optionally polls instance/system status checks until all are ok
  • Idempotency notes: reboot is inherently mutating but safe for repeated execution under incident control.
  • Side effects: transient service interruption during restart cycle.

Output

  • Standard output format: timestamped operational logs on stderr.
  • Exit codes:
  • 0 success
  • 2 invalid arguments/state preconditions
  • non-zero on AWS/API or wait timeout failures

Failure Modes

  • Common errors and likely causes:
  • reboot requested for non-running instance
  • prolonged degraded instance/system checks
  • insufficient reboot permissions
  • Recovery and rollback steps:
  • verify state and permissions, then retry
  • escalate to stop/start or restore procedures if checks remain unhealthy

Security Notes

  • Secret handling: none.
  • Least-privilege requirements: reboot and describe permissions on allowed instances only.
  • Audit/logging expectations: reboot actions should be tied to incident/change tracking.

Testing

  • Unit tests:
  • ID parsing and state validation
  • wait timeout/poll logic
  • Integration tests:
  • reboot path and status-check convergence in test account
  • Manual verification:
  • confirm InstanceStatus.Status=ok and SystemStatus.Status=ok
stop-instance.sh resize-instance.sh