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@samkeen
Created April 10, 2019 15:58
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Ec2InPrivateSubnetWithouttNatGtwy:
Type: AWS::EC2::Instance
Properties:
ImageId: !Ref LatestAmiId
InstanceType: !Ref InstanceType
# KeyName: NO SSH Key needed
IamInstanceProfile: !Ref Ec2InstanceProfile
NetworkInterfaces:
# The SSM Agent running on the EC2 instances must be able to connect to Session Manager's
# public endpoint. You can also set up a PrivateLink connection to allow instances running
# in private VPCs (without Internet access or a public IP address) to connect to Session Manager.
# Here the instance is in a private subnet with a default route to the NAT Gateway so we can use that to
# connect to the SSM's public endpoint
- AssociatePublicIpAddress: false
DeviceIndex: 0
GroupSet:
- !Ref Ec2InstanceSecurityGroup
SubnetId: !Ref PrivateSubnetWithoutNat
Tags:
- Key: Name
Value: Session Manager test Instnace in Private Subnet without NatGtwy
# In this case we've chosen to set up CloudWatch Logs for the SSM agent logs
UserData:
Fn::Base64: !Sub |
#!/bin/bash -xe
# Get the latest CloudFormation package
yum update -y aws-cfn-bootstrap
# Start cfn-init
/opt/aws/bin/cfn-init -s ${AWS::StackId} -r Ec2Instance --region ${AWS::Region} || error_exit 'Failed to run cfn-init'
# make the needed dir for the cwlogs state_file
mkdir /var/awslogs
# Get the CloudWatch Logs agent
yum install -y awslogs
# overwrite awscli.conf with our copy
mv /etc/awslogs/awscli.replace.conf /etc/awslogs/awscli.conf
# Install the CloudWatch Logs agent (works with AWS Linux[1] or 2)
if command -v systemctl >/dev/null; then systemctl start awslogsd; else service awslogs start; fi
# Enable start on reboot (works with AWS Linux[1] or 2)
if command -v systemctl >/dev/null; then systemctl enable awslogsd.service; else chkconfig awslogs on; fi
# change the login shell for ssm-user, although amazon-ssm-agent still forces /bin/sh
# https://github.com/aws/amazon-ssm-agent/issues/131
usermod --shell /bin/bash ssm-user
# All done so signal success
/opt/aws/bin/cfn-signal -e $? --stack ${AWS::StackId} --resource Ec2Instance --region ${AWS::Region}
Metadata:
Comment: Install configure CWLogs
AWS::CloudFormation::Init:
config:
files:
# Build our CWLogs Agent Configuration File, used in cloud init UserData below
# see https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/AgentReference.html
"/etc/awslogs/awslogs.conf":
content: !Sub |
# writen by aws clodformation stack ${AWS::StackId}
[general]
state_file = /var/awslogs/agent-state
# SSM Agent Logs
# https://docs.aws.amazon.com/systems-manager/latest/userguide/sysman-agent-logs.html
[/var/log/amazon/ssm/amazon-ssm-agent.log]
file = /var/log/amazon/ssm/amazon-ssm-agent.log
log_group_name = ${Ec2InstanceSsmAgentLogGroup}
log_stream_name = {instance_id}/ssm-agent.log
datetime_format = %Y-%m-%d %H:%M:%S
[/var/log/amazon/ssm/errors.log]
file = /var/log/amazon/ssm/errors.log
log_group_name = ${Ec2InstanceSsmErrorLogGroup}
log_stream_name = {instance_id}/ssm-error.log
datetime_format = %Y-%m-%d %H:%M:%S
# The log group will be created in region specified in /etc/awslogs/awscli.conf
# write this temp file we will move into place in cloud init script below
"/etc/awslogs/awscli.replace.conf":
content: !Sub |
# writen by aws clodformation stack ${AWS::StackId}
[plugins]
cwlogs = cwlogs
[default]
region = ${AWS::Region}
Ec2InstanceSsmAgentLogGroup:
Type: AWS::Logs::LogGroup
Properties:
RetentionInDays: 7
Ec2InstanceSsmErrorLogGroup:
Type: AWS::Logs::LogGroup
Properties:
RetentionInDays: 7
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