从最新快照还原根卷 - AWS Systems Manager

从最新快照还原根卷

根卷上的操作系统可能会出于各种原因而受损。例如，在执行修补操作后，实例可能会因内核或注册表损坏而无法成功启动。自动执行常见故障排除任务（例如，从修补操作前拍摄的最新快照还原根卷）可以减少停机时间并加快故障排除工作。AWS Systems Manager自动化操作可帮助您做到这一点。自动化是 AWS Systems Manager 的一项功能。

以下示例 AWS Systems Manager 运行手册执行这些操作：

  • 使用 aws:executeAwsApi 自动化操作从实例的根卷检索详细信息。

  • 使用 aws:executeScript 自动化操作检索根卷的最新快照。

  • 如果找到了根卷的快照，则使用 aws:branch 自动化操作继续执行自动化。

YAML

    ---
    description: Custom Automation Troubleshooting Example
    schemaVersion: '0.3'
    assumeRole: "{{ AutomationAssumeRole }}"
    parameters:
      AutomationAssumeRole:
        type: String
        description: "(Required) The ARN of the role that allows Automation to perform
          the actions on your behalf. If no role is specified, Systems Manager Automation
          uses your IAM permissions to use this runbook."
        default: ''
      InstanceId:
          type: String
          description: "(Required) The Instance Id whose root EBS volume you want to restore the latest Snapshot."
          default: ''
    mainSteps:
    - name: getInstanceDetails
      action: aws:executeAwsApi
      onFailure: Abort
      inputs:
        Service: ec2
        Api: DescribeInstances
        InstanceIds:
        - "{{ InstanceId }}"
      outputs:
        - Name: availabilityZone
          Selector: "$.Reservations[0].Instances[0].Placement.AvailabilityZone"
          Type: String
        - Name: rootDeviceName
          Selector: "$.Reservations[0].Instances[0].RootDeviceName"
          Type: String
      nextStep: getRootVolumeId
    - name: getRootVolumeId
      action: aws:executeAwsApi
      onFailure: Abort
      inputs:
        Service: ec2
        Api: DescribeVolumes
        Filters:
        -  Name: attachment.device
           Values: ["{{ getInstanceDetails.rootDeviceName }}"]
        -  Name: attachment.instance-id
           Values: ["{{ InstanceId }}"]
      outputs:
        - Name: rootVolumeId
          Selector: "$.Volumes[0].VolumeId"
          Type: String
      nextStep: getSnapshotsByStartTime
    - name: getSnapshotsByStartTime
      action: aws:executeScript
      timeoutSeconds: 45
      onFailure: Abort
      inputs:
        Runtime: python3.8
        Handler: getSnapshotsByStartTime
        InputPayload:
          rootVolumeId : "{{ getRootVolumeId.rootVolumeId }}"
        Script: |-
          def getSnapshotsByStartTime(events,context):
            import boto3
    
            #Initialize client
            ec2 = boto3.client('ec2')
            rootVolumeId = events['rootVolumeId']
            snapshotsQuery = ec2.describe_snapshots(
              Filters=[
                {
                  "Name": "volume-id",
                  "Values": [rootVolumeId]
                }
              ]
            )
            if not snapshotsQuery['Snapshots']:
              noSnapshotFoundString = "NoSnapshotFound"
              return { 'noSnapshotFound' : noSnapshotFoundString }
            else:
              jsonSnapshots = snapshotsQuery['Snapshots']
              sortedSnapshots = sorted(jsonSnapshots, key=lambda k: k['StartTime'], reverse=True)
              latestSortedSnapshotId = sortedSnapshots[0]['SnapshotId']
              return { 'latestSnapshotId' : latestSortedSnapshotId }
      outputs:
      - Name: Payload
        Selector: $.Payload
        Type: StringMap
      - Name: latestSnapshotId
        Selector: $.Payload.latestSnapshotId
        Type: String
      - Name: noSnapshotFound
        Selector: $.Payload.noSnapshotFound
        Type: String 
      nextStep: branchFromResults
    - name: branchFromResults
      action: aws:branch
      onFailure: Abort
      inputs:
        Choices:
        - NextStep: createNewRootVolumeFromSnapshot
          Not:
            Variable: "{{ getSnapshotsByStartTime.noSnapshotFound }}"
            StringEquals: "NoSnapshotFound"
      isEnd: true
    - name: createNewRootVolumeFromSnapshot
      action: aws:executeAwsApi
      onFailure: Abort
      inputs:
        Service: ec2
        Api: CreateVolume
        AvailabilityZone: "{{ getInstanceDetails.availabilityZone }}"
        SnapshotId: "{{ getSnapshotsByStartTime.latestSnapshotId }}"
      outputs:
        - Name: newRootVolumeId
          Selector: "$.VolumeId"
          Type: String
      nextStep: stopInstance
    - name: stopInstance
      action: aws:executeAwsApi
      onFailure: Abort
      inputs:
        Service: ec2
        Api: StopInstances
        InstanceIds:
        - "{{ InstanceId }}"
      nextStep: verifyVolumeAvailability
    - name: verifyVolumeAvailability
      action: aws:waitForAwsResourceProperty
      timeoutSeconds: 120
      inputs:
        Service: ec2
        Api: DescribeVolumes
        VolumeIds:
        - "{{ createNewRootVolumeFromSnapshot.newRootVolumeId }}"
        PropertySelector: "$.Volumes[0].State"
        DesiredValues:
        - "available"
      nextStep: verifyInstanceStopped
    - name: verifyInstanceStopped
      action: aws:waitForAwsResourceProperty
      timeoutSeconds: 120
      inputs:
        Service: ec2
        Api: DescribeInstances
        InstanceIds:
        - "{{ InstanceId }}"
        PropertySelector: "$.Reservations[0].Instances[0].State.Name"
        DesiredValues:
        - "stopped"
      nextStep: detachRootVolume
    - name: detachRootVolume
      action: aws:executeAwsApi
      onFailure: Abort
      inputs:
        Service: ec2
        Api: DetachVolume
        VolumeId: "{{ getRootVolumeId.rootVolumeId }}"
      nextStep: verifyRootVolumeDetached
    - name: verifyRootVolumeDetached
      action: aws:waitForAwsResourceProperty
      timeoutSeconds: 30
      inputs:
        Service: ec2
        Api: DescribeVolumes
        VolumeIds:
        - "{{ getRootVolumeId.rootVolumeId }}"
        PropertySelector: "$.Volumes[0].State"
        DesiredValues:
        - "available"
      nextStep: attachNewRootVolume
    - name: attachNewRootVolume
      action: aws:executeAwsApi
      onFailure: Abort
      inputs:
        Service: ec2
        Api: AttachVolume
        Device: "{{ getInstanceDetails.rootDeviceName }}"
        InstanceId: "{{ InstanceId }}"
        VolumeId: "{{ createNewRootVolumeFromSnapshot.newRootVolumeId }}"
      nextStep: verifyNewRootVolumeAttached
    - name: verifyNewRootVolumeAttached
      action: aws:waitForAwsResourceProperty
      timeoutSeconds: 30
      inputs:
        Service: ec2
        Api: DescribeVolumes
        VolumeIds:
        - "{{ createNewRootVolumeFromSnapshot.newRootVolumeId }}"
        PropertySelector: "$.Volumes[0].Attachments[0].State"
        DesiredValues:
        - "attached"
      nextStep: startInstance
    - name: startInstance
      action: aws:executeAwsApi
      onFailure: Abort
      inputs:
        Service: ec2
        Api: StartInstances
        InstanceIds:
        - "{{ InstanceId }}"
JSON

    {
       "description": "Custom Automation Troubleshooting Example",
       "schemaVersion": "0.3",
       "assumeRole": "{{ AutomationAssumeRole }}",
       "parameters": {
          "AutomationAssumeRole": {
             "type": "String",
             "description": "(Required) The ARN of the role that allows Automation to perform the actions on your behalf. If no role is specified, Systems Manager Automation uses your IAM permissions to run this runbook.",
             "default": ""
          },
          "InstanceId": {
             "type": "String",
             "description": "(Required) The Instance Id whose root EBS volume you want to restore the latest Snapshot.",
             "default": ""
          }
       },
       "mainSteps": [
          {
             "name": "getInstanceDetails",
             "action": "aws:executeAwsApi",
             "onFailure": "Abort",
             "inputs": {
                "Service": "ec2",
                "Api": "DescribeInstances",
                "InstanceIds": [
                   "{{ InstanceId }}"
                ]
             },
             "outputs": [
                {
                   "Name": "availabilityZone",
                   "Selector": "$.Reservations[0].Instances[0].Placement.AvailabilityZone",
                   "Type": "String"
                },
                {
                   "Name": "rootDeviceName",
                   "Selector": "$.Reservations[0].Instances[0].RootDeviceName",
                   "Type": "String"
                }
             ],
             "nextStep": "getRootVolumeId"
          },
          {
             "name": "getRootVolumeId",
             "action": "aws:executeAwsApi",
             "onFailure": "Abort",
             "inputs": {
                "Service": "ec2",
                "Api": "DescribeVolumes",
                "Filters": [
                   {
                      "Name": "attachment.device",
                      "Values": [
                         "{{ getInstanceDetails.rootDeviceName }}"
                      ]
                   },
                   {
                      "Name": "attachment.instance-id",
                      "Values": [
                         "{{ InstanceId }}"
                      ]
                   }
                ]
             },
             "outputs": [
                {
                   "Name": "rootVolumeId",
                   "Selector": "$.Volumes[0].VolumeId",
                   "Type": "String"
                }
             ],
             "nextStep": "getSnapshotsByStartTime"
          },
          {
             "name": "getSnapshotsByStartTime",
             "action": "aws:executeScript",
             "timeoutSeconds": 45,
             "onFailure": "Continue",
             "inputs": {
                "Runtime": "python3.8",
                "Handler": "getSnapshotsByStartTime",
                "InputPayload": {
                   "rootVolumeId": "{{ getRootVolumeId.rootVolumeId }}"
                },
                "Attachment": "getSnapshotsByStartTime.py"
             },
             "outputs": [
                {
                   "Name": "Payload",
                   "Selector": "$.Payload",
                   "Type": "StringMap"
                },
                {
                   "Name": "latestSnapshotId",
                   "Selector": "$.Payload.latestSnapshotId",
                   "Type": "String"
                },
                {
                   "Name": "noSnapshotFound",
                   "Selector": "$.Payload.noSnapshotFound",
                   "Type": "String"
                }
             ],
             "nextStep": "branchFromResults"
          },
          {
             "name": "branchFromResults",
             "action": "aws:branch",
             "onFailure": "Abort",
             "inputs": {
                "Choices": [
                   {
                      "NextStep": "createNewRootVolumeFromSnapshot",
                      "Not": {
                         "Variable": "{{ getSnapshotsByStartTime.noSnapshotFound }}",
                         "StringEquals": "NoSnapshotFound"
                      }
                   }
                ]
             },
             "isEnd": true
          },
          {
             "name": "createNewRootVolumeFromSnapshot",
             "action": "aws:executeAwsApi",
             "onFailure": "Abort",
             "inputs": {
                "Service": "ec2",
                "Api": "CreateVolume",
                "AvailabilityZone": "{{ getInstanceDetails.availabilityZone }}",
                "SnapshotId": "{{ getSnapshotsByStartTime.latestSnapshotId }}"
             },
             "outputs": [
                {
                   "Name": "newRootVolumeId",
                   "Selector": "$.VolumeId",
                   "Type": "String"
                }
             ],
             "nextStep": "stopInstance"
          },
          {
             "name": "stopInstance",
             "action": "aws:executeAwsApi",
             "onFailure": "Abort",
             "inputs": {
                "Service": "ec2",
                "Api": "StopInstances",
                "InstanceIds": [
                   "{{ InstanceId }}"
                ]
             },
             "nextStep": "verifyVolumeAvailability"
          },
          {
             "name": "verifyVolumeAvailability",
             "action": "aws:waitForAwsResourceProperty",
             "timeoutSeconds": 120,
             "inputs": {
                "Service": "ec2",
                "Api": "DescribeVolumes",
                "VolumeIds": [
                   "{{ createNewRootVolumeFromSnapshot.newRootVolumeId }}"
                ],
                "PropertySelector": "$.Volumes[0].State",
                "DesiredValues": [
                   "available"
                ]
             },
             "nextStep": "verifyInstanceStopped"
          },
          {
             "name": "verifyInstanceStopped",
             "action": "aws:waitForAwsResourceProperty",
             "timeoutSeconds": 120,
             "inputs": {
                "Service": "ec2",
                "Api": "DescribeInstances",
                "InstanceIds": [
                   "{{ InstanceId }}"
                ],
                "PropertySelector": "$.Reservations[0].Instances[0].State.Name",
                "DesiredValues": [
                   "stopped"
                ]
             },
             "nextStep": "detachRootVolume"
          },
          {
             "name": "detachRootVolume",
             "action": "aws:executeAwsApi",
             "onFailure": "Abort",
             "inputs": {
                "Service": "ec2",
                "Api": "DetachVolume",
                "VolumeId": "{{ getRootVolumeId.rootVolumeId }}"
             },
             "nextStep": "verifyRootVolumeDetached"
          },
          {
             "name": "verifyRootVolumeDetached",
             "action": "aws:waitForAwsResourceProperty",
             "timeoutSeconds": 30,
             "inputs": {
                "Service": "ec2",
                "Api": "DescribeVolumes",
                "VolumeIds": [
                   "{{ getRootVolumeId.rootVolumeId }}"
                ],
                "PropertySelector": "$.Volumes[0].State",
                "DesiredValues": [
                   "available"
                ]
             },
             "nextStep": "attachNewRootVolume"
          },
          {
             "name": "attachNewRootVolume",
             "action": "aws:executeAwsApi",
             "onFailure": "Abort",
             "inputs": {
                "Service": "ec2",
                "Api": "AttachVolume",
                "Device": "{{ getInstanceDetails.rootDeviceName }}",
                "InstanceId": "{{ InstanceId }}",
                "VolumeId": "{{ createNewRootVolumeFromSnapshot.newRootVolumeId }}"
             },
             "nextStep": "verifyNewRootVolumeAttached"
          },
          {
             "name": "verifyNewRootVolumeAttached",
             "action": "aws:waitForAwsResourceProperty",
             "timeoutSeconds": 30,
             "inputs": {
                "Service": "ec2",
                "Api": "DescribeVolumes",
                "VolumeIds": [
                   "{{ createNewRootVolumeFromSnapshot.newRootVolumeId }}"
                ],
                "PropertySelector": "$.Volumes[0].Attachments[0].State",
                "DesiredValues": [
                   "attached"
                ]
             },
             "nextStep": "startInstance"
          },
          {
             "name": "startInstance",
             "action": "aws:executeAwsApi",
             "onFailure": "Abort",
             "inputs": {
                "Service": "ec2",
                "Api": "StartInstances",
                "InstanceIds": [
                   "{{ InstanceId }}"
                ]
             }
          }
       ],
       "files": {
            "getSnapshotsByStartTime.py": {
                "checksums": {
                    "sha256": "sampleETagValue"
                }
            }
        }
    }