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A CloudFormation template for CentOS 7 showing AMI mappings and cloud-init UserData parsing
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| AWSTemplateFormatVersion: 2010-09-09 | |
| Description: > | |
| An example free tier (12 month) CentOS 7 EC2 instance with a security group | |
| allowing SSH, a simple IAM Role, and output conveyed from the launch back out | |
| to the CloudFormation stack outputs | |
| Parameters: | |
| SSHKeyName: | |
| Description: SSH Key Name | |
| Type: String | |
| Mappings: | |
| # This list of AMI IDs was produced with this code | |
| # https://gist.github.com/gene1wood/56e42097e0f0ac1aace14cbc41ee3e11#file-create_centos7_cloudformation_ami_mapping-py | |
| RegionMap: | |
| ap-northeast-1: | |
| CentOS7x8664EBSHVM: ami-045f38c93733dd48d | |
| ap-northeast-2: | |
| CentOS7x8664EBSHVM: ami-06cf2a72dadf92410 | |
| ap-south-1: | |
| CentOS7x8664EBSHVM: ami-02e60be79e78fef21 | |
| ap-southeast-1: | |
| CentOS7x8664EBSHVM: ami-0b4dd9d65556cac22 | |
| ap-southeast-2: | |
| CentOS7x8664EBSHVM: ami-08bd00d7713a39e7d | |
| ca-central-1: | |
| CentOS7x8664EBSHVM: ami-033e6106180a626d0 | |
| eu-central-1: | |
| CentOS7x8664EBSHVM: ami-04cf43aca3e6f3de3 | |
| eu-north-1: | |
| CentOS7x8664EBSHVM: ami-5ee66f20 | |
| eu-west-1: | |
| CentOS7x8664EBSHVM: ami-0ff760d16d9497662 | |
| eu-west-2: | |
| CentOS7x8664EBSHVM: ami-0eab3a90fc693af19 | |
| eu-west-3: | |
| CentOS7x8664EBSHVM: ami-0e1ab783dc9489f34 | |
| sa-east-1: | |
| CentOS7x8664EBSHVM: ami-0b8d86d4bf91850af | |
| us-east-1: | |
| CentOS7x8664EBSHVM: ami-02eac2c0129f6376b | |
| us-east-2: | |
| CentOS7x8664EBSHVM: ami-0f2b4fc905b0bd1f1 | |
| us-west-1: | |
| CentOS7x8664EBSHVM: ami-074e2d6769f445be5 | |
| us-west-2: | |
| CentOS7x8664EBSHVM: ami-01ed306a12b7d1c96 | |
| Resources: | |
| SecurityGroup: | |
| Type: AWS::EC2::SecurityGroup | |
| Properties: | |
| GroupDescription: Security Group | |
| SecurityGroupIngress: | |
| - FromPort: 22 | |
| ToPort: 22 | |
| IpProtocol: tcp | |
| CidrIp: '0.0.0.0/0' | |
| Instance: | |
| Type: AWS::EC2::Instance | |
| Metadata: | |
| UserDataComment1: The cloud-config script is delivered directly in user_data | |
| because the CentOS 7 base AMIs run cloud-init automatically, looking for a | |
| cloud-init config in user_data | |
| UserDataComment2: In this example the 'dmidecode' command is run and the output | |
| is sent back to the WaitConditionHandle which is then passed out through the | |
| CloudFormation outputs | |
| Properties: | |
| ImageId: !FindInMap [ RegionMap, !Ref 'AWS::Region', CentOS7x8664EBSHVM ] | |
| InstanceType: t2.micro # Instance size of the free tier for 12 months | |
| BlockDeviceMappings: | |
| - DeviceName: /dev/sda1 | |
| Ebs: | |
| VolumeType: gp2 | |
| DeleteOnTermination: false | |
| VolumeSize: 30 # Free tier provides 30GiB of gp2 or standard EBS | |
| KeyName: !Ref SSHKeyName | |
| SecurityGroups: | |
| - !Ref SecurityGroup | |
| IamInstanceProfile: !Ref InstanceProfile | |
| UserData: | |
| Fn::Base64: !Sub | | |
| #cloud-config | |
| packages: | |
| - awscli | |
| runcmd: | |
| - > | |
| for i in {1..3}; do /usr/bin/easy_install | |
| https://s3.amazonaws.com/cloudformation-examples/aws-cfn-bootstrap-latest.tar.gz | |
| 2>&1 >> /var/log/initial_user-data.log && break || sleep 10; done | |
| - aws --region us-west-2 ec2 describe-regions --output text >> /tmp/custom-output.txt | |
| - CFNSTATUS=$? | |
| - > | |
| /usr/bin/cfn-signal | |
| --exit-code $CFNSTATUS | |
| --data "$( < /tmp/custom-output.txt )" | |
| "${WaitConditionHandle}" 2>&1 >> /var/log/initial_user-data.log | |
| Role: | |
| Type: AWS::IAM::Role | |
| Properties: | |
| AssumeRolePolicyDocument: | |
| Version: 2012-10-17 | |
| Statement: | |
| - Effect: Allow | |
| Principal: | |
| Service: ec2.amazonaws.com | |
| Action: sts:AssumeRole | |
| Policies: | |
| - PolicyName: DescribeRegions | |
| PolicyDocument: | |
| Version: 2012-10-17 | |
| Statement: | |
| - Sid: AllowEC2DescribeRegions | |
| Effect: Allow | |
| Action: | |
| - ec2:DescribeRegions | |
| Resource: '*' | |
| InstanceProfile: | |
| Type: AWS::IAM::InstanceProfile | |
| Properties: | |
| Roles: | |
| - !Ref Role | |
| WaitConditionHandle: | |
| Type: AWS::CloudFormation::WaitConditionHandle | |
| WaitCondition: | |
| Type: AWS::CloudFormation::WaitCondition | |
| DependsOn: Instance | |
| Properties: | |
| Handle: !Ref WaitConditionHandle | |
| Timeout: '300' | |
| Outputs: | |
| CloudInitOutput: | |
| Description: The data returned to the WaitConditionHandle from Cloud Init | |
| Value: !GetAtt WaitCondition.Data | |
| EC2InstancePublicDNSName: | |
| Description: The public DNS name of the instance | |
| Value: !GetAtt Instance.PublicDnsName |
Not sure if this was intentional, but there are two AIM missing in your mapping:
Asia Pacific (Mumbai) ami-95cda6fa
US East (Ohio) ami-6a2d760f
I tried this, as written, and it times out and rolls back. I could sure use some help understanding what is failing. The log files are below.
initial_user-data.log
Downloading https://s3.amazonaws.com/cloudformation-examples/aws-cfn-bootstrap-latest.tar.gz
Processing aws-cfn-bootstrap-latest.tar.gz
Writing /tmp/easy_install-cHTPlA/aws-cfn-bootstrap-1.4/setup.cfg
Running aws-cfn-bootstrap-1.4/setup.py -q bdist_egg --dist-dir /tmp/easy_install-cHTPlA/aws-cfn-bootstrap-1.4/egg-dist-tmp-LR21FA
Adding aws-cfn-bootstrap 1.4 to easy-install.pth file
Installing cfn-init script to /usr/bin
Installing cfn-signal script to /usr/bin
Installing cfn-get-metadata script to /usr/bin
Installing cfn-hup script to /usr/bin
Installing cfn-elect-cmd-leader script to /usr/bin
Installing cfn-send-cmd-result script to /usr/bin
Installing cfn-send-cmd-event script to /usr/bin
Installed /usr/lib/python2.7/site-packages/aws_cfn_bootstrap-1.4-py2.7.egg
Processing dependencies for aws-cfn-bootstrap==1.4
Searching for pystache>=0.4.0
Reading https://pypi.python.org/simple/pystache/
Best match: pystache 0.5.4
Downloading https://pypi.python.org/packages/d6/fd/eb8c212053addd941cc90baac307c00ac246ac3fce7166b86434c6eae963/pystache-0.5.4.tar.gz#md5=485885e67a0f6411d5252e69b20a35ca
Processing pystache-0.5.4.tar.gz
Writing /tmp/easy_install-4XGsWd/pystache-0.5.4/setup.cfg
Running pystache-0.5.4/setup.py -q bdist_egg --dist-dir /tmp/easy_install-4XGsWd/pystache-0.5.4/egg-dist-tmp-dli6k7
Adding pystache 0.5.4 to easy-install.pth file
Installing pystache script to /usr/bin
Installing pystache-test script to /usr/bin
Installed /usr/lib/python2.7/site-packages/pystache-0.5.4-py2.7.egg
Searching for python-daemon>=1.5.2,<2.0
Reading https://pypi.python.org/simple/python-daemon/
Best match: python-daemon 1.6.1
Downloading https://pypi.python.org/packages/b8/e2/bd862c723451121f41cf53d87a9f2c69eeb97358fb4477b929878804b8a3/python-daemon-1.6.1.tar.gz#md5=cbad567c105878776b567535a8b7372a
Processing python-daemon-1.6.1.tar.gz
Writing /tmp/easy_install-dl799F/python-daemon-1.6.1/setup.cfg
Running python-daemon-1.6.1/setup.py -q bdist_egg --dist-dir /tmp/easy_install-dl799F/python-daemon-1.6.1/egg-dist-tmp-IZWRk7
Adding python-daemon 1.6.1 to easy-install.pth file
Installed /usr/lib/python2.7/site-packages/python_daemon-1.6.1-py2.7.egg
Searching for lockfile>=0.9
Reading https://pypi.python.org/simple/lockfile/
Best match: lockfile 0.12.2
Downloading https://pypi.python.org/packages/17/47/72cb04a58a35ec495f96984dddb48232b551aafb95bde614605b754fe6f7/lockfile-0.12.2.tar.gz#md5=a6a1a82957a23afdf44cfdd039b65ff9
Processing lockfile-0.12.2.tar.gz
Writing /tmp/easy_install-8mxYNh/lockfile-0.12.2/setup.cfg
Running lockfile-0.12.2/setup.py -q bdist_egg --dist-dir /tmp/easy_install-8mxYNh/lockfile-0.12.2/egg-dist-tmp-rfLQ7a
Searching for pbr>=1.8
Reading https://pypi.python.org/simple/pbr/
Best match: pbr 3.1.1
Downloading https://pypi.python.org/packages/d5/d6/f2bf137d71e4f213b575faa9eb426a8775732432edb67588a8ee836ecb80/pbr-3.1.1.tar.gz#md5=4e82c2e07af544c56a5b71c801525b00
Processing pbr-3.1.1.tar.gz
Writing /tmp/easy_install-8mxYNh/lockfile-0.12.2/temp/easy_install-JtYloG/pbr-3.1.1/setup.cfg
Running pbr-3.1.1/setup.py -q bdist_egg --dist-dir /tmp/easy_install-8mxYNh/lockfile-0.12.2/temp/easy_install-JtYloG/pbr-3.1.1/egg-dist-tmp-IVRvhU
Installed /tmp/easy_install-8mxYNh/lockfile-0.12.2/pbr-3.1.1-py2.7.egg
Adding lockfile 0.12.2 to easy-install.pth file
Installed /usr/lib/python2.7/site-packages/lockfile-0.12.2-py2.7.egg
Finished processing dependencies for aws-cfn-bootstrap==1.4
cloud-init.txt
Aug 22 00:22:57 localhost cloud-init: Cloud-init v. 0.7.5 running 'init-local' at Tue, 22 Aug 2017 00:22:57 +0000. Up 18.69 seconds.
Aug 22 00:23:00 localhost cloud-init: Cloud-init v. 0.7.5 running 'init' at Tue, 22 Aug 2017 00:23:00 +0000. Up 21.32 seconds.
Aug 22 00:23:00 localhost cloud-init: ci-info: ++++++++++++++++++++++++++Net device info+++++++++++++++++++++++++++
Aug 22 00:23:00 localhost cloud-init: ci-info: +--------+------+--------------+---------------+-------------------+
Aug 22 00:23:01 localhost cloud-init: ci-info: | Device | Up | Address | Mask | Hw-Address |
Aug 22 00:23:01 localhost cloud-init: ci-info: +--------+------+--------------+---------------+-------------------+
Aug 22 00:23:01 localhost cloud-init: ci-info: | lo: | True | 127.0.0.1 | 255.0.0.0 | . |
Aug 22 00:23:01 localhost cloud-init: ci-info: | eth0: | True | 172.31.44.94 | 255.255.240.0 | 0a:dd:94:e6:5b:a2 |
Aug 22 00:23:01 localhost cloud-init: ci-info: +--------+------+--------------+---------------+-------------------+
Aug 22 00:23:01 localhost cloud-init: ci-info: +++++++++++++++++++++++++++++++Route info++++++++++++++++++++++++++++++++
Aug 22 00:23:01 localhost cloud-init: ci-info: +-------+-------------+-------------+---------------+-----------+-------+
Aug 22 00:23:01 localhost cloud-init: ci-info: | Route | Destination | Gateway | Genmask | Interface | Flags |
Aug 22 00:23:01 localhost cloud-init: ci-info: +-------+-------------+-------------+---------------+-----------+-------+
Aug 22 00:23:01 localhost cloud-init: ci-info: | 0 | 0.0.0.0 | 172.31.32.1 | 0.0.0.0 | eth0 | UG |
Aug 22 00:23:01 localhost cloud-init: ci-info: | 1 | 172.31.32.0 | 0.0.0.0 | 255.255.240.0 | eth0 | U |
Aug 22 00:23:01 localhost cloud-init: ci-info: +-------+-------------+-------------+---------------+-----------+-------+
Aug 22 00:23:05 localhost cloud-init: Cloud-init v. 0.7.5 running 'modules:config' at Tue, 22 Aug 2017 00:23:05 +0000. Up 26.72 seconds.
Aug 22 00:23:06 localhost cloud-init: Cloud-init v. 0.7.5 running 'modules:final' at Tue, 22 Aug 2017 00:23:06 +0000. Up 27.40 seconds.
Aug 22 00:23:08 localhost cloud-init: zip_safe flag not set; analyzing archive contents...
Aug 22 00:23:08 localhost cloud-init: cfnbootstrap.packages.requests.certs: module references __file__
Aug 22 00:23:08 localhost cloud-init: cfnbootstrap.packages.requests.certs: module references __file__
Aug 22 00:23:09 localhost cloud-init: pystache: using: version '0.9.8' of <module 'setuptools' from '/usr/lib/python2.7/site-packages/setuptools/__init__.pyc'>
Aug 22 00:23:09 localhost cloud-init: zip_safe flag not set; analyzing archive contents...
Aug 22 00:23:09 localhost cloud-init: pystache.locator: module references __file__
Aug 22 00:23:09 localhost cloud-init: pystache.tests.common: module references __file__
Aug 22 00:23:12 localhost cloud-init: Usage: cfn-signal [options] [WaitConditionHandle URL]
Aug 22 00:23:12 localhost cloud-init: cfn-signal: error: option --exit-code: invalid integer value: '--data'
Aug 22 00:23:12 localhost cloud-init: 2017-08-22 00:23:12,378 - util.py[WARNING]: Failed running /var/lib/cloud/instance/scripts/runcmd [2]
Aug 22 00:23:12 localhost cloud-init: 2017-08-22 00:23:12,406 - cc_scripts_user.py[WARNING]: Failed to run module scripts-user (scripts in /var/lib/cloud/instance/scripts)
Aug 22 00:23:12 localhost cloud-init: 2017-08-22 00:23:12,407 - util.py[WARNING]: Running scripts-user (<module 'cloudinit.config.cc_scripts_user' from '/usr/lib/python2.7/site-packages/cloudinit/config/cc_scripts_user.pyc'>) failed
Aug 22 00:23:13 localhost cloud-init: Cloud-init v. 0.7.5 finished at Tue, 22 Aug 2017 00:23:13 +0000. Datasource DataSourceEc2. Up 34.45 seconds
cloud-init-output.txt
Cloud-init v. 0.7.5 running 'init-local' at Tue, 22 Aug 2017 00:22:57 +0000. Up 18.69 seconds.
Cloud-init v. 0.7.5 running 'init' at Tue, 22 Aug 2017 00:23:00 +0000. Up 21.32 seconds.
ci-info: ++++++++++++++++++++++++++Net device info+++++++++++++++++++++++++++
ci-info: +--------+------+--------------+---------------+-------------------+
ci-info: | Device | Up | Address | Mask | Hw-Address |
ci-info: +--------+------+--------------+---------------+-------------------+
ci-info: | lo: | True | 127.0.0.1 | 255.0.0.0 | . |
ci-info: | eth0: | True | 172.31.44.94 | 255.255.240.0 | 0a:dd:94:e6:5b:a2 |
ci-info: +--------+------+--------------+---------------+-------------------+
ci-info: +++++++++++++++++++++++++++++++Route info++++++++++++++++++++++++++++++++
ci-info: +-------+-------------+-------------+---------------+-----------+-------+
ci-info: | Route | Destination | Gateway | Genmask | Interface | Flags |
ci-info: +-------+-------------+-------------+---------------+-----------+-------+
ci-info: | 0 | 0.0.0.0 | 172.31.32.1 | 0.0.0.0 | eth0 | UG |
ci-info: | 1 | 172.31.32.0 | 0.0.0.0 | 255.255.240.0 | eth0 | U |
ci-info: +-------+-------------+-------------+---------------+-----------+-------+
Cloud-init v. 0.7.5 running 'modules:config' at Tue, 22 Aug 2017 00:23:05 +0000. Up 26.72 seconds.
Cloud-init v. 0.7.5 running 'modules:final' at Tue, 22 Aug 2017 00:23:06 +0000. Up 27.40 seconds.
zip_safe flag not set; analyzing archive contents...
cfnbootstrap.packages.requests.certs: module references __file__
cfnbootstrap.packages.requests.certs: module references __file__
pystache: using: version '0.9.8' of <module 'setuptools' from '/usr/lib/python2.7/site-packages/setuptools/__init__.pyc'>
zip_safe flag not set; analyzing archive contents...
pystache.locator: module references __file__
pystache.tests.common: module references __file__
Usage: cfn-signal [options] [WaitConditionHandle URL]
cfn-signal: error: option --exit-code: invalid integer value: '--data'
2017-08-22 00:23:12,378 - util.py[WARNING]: Failed running /var/lib/cloud/instance/scripts/runcmd [2]
2017-08-22 00:23:12,406 - cc_scripts_user.py[WARNING]: Failed to run module scripts-user (scripts in /var/lib/cloud/instance/scripts)
2017-08-22 00:23:12,407 - util.py[WARNING]: Running scripts-user (<module 'cloudinit.config.cc_scripts_user' from '/usr/lib/python2.7/site-packages/cloudinit/config/cc_scripts_user.pyc'>) failed
Cloud-init v. 0.7.5 finished at Tue, 22 Aug 2017 00:23:13 +0000. Datasource DataSourceEc2. Up 34.45 seconds
I found what's wrong with the above. The clue is in the line cfn-signal: error: option --exit-code: invalid integer value: '--data'
In the template, we have this:
"UserData":{
"Fn::Base64":{
"Fn::Join":[
"",
[
"#cloud-config\n",
"\n",
"runcmd:\n",
" - for i in {1..3}; do /usr/bin/easy_install https://s3.amazonaws.com/cloudformation-examples/aws-cfn-bootstrap-latest.tar.gz 2>&1 >> /var/log/initial_user-data.log && break || sleep 10; done\n",
" - dmidecode 2>&1 >> /tmp/custom-output.txt",
" - CFNSTATUS=$?\n",
" - /usr/bin/cfn-signal ",
" --exit-code $CFNSTATUS ",
" --data \"$( base64 -w 0 /tmp/custom-output.txt )\" ",
"'",
{
"Ref":"WaitConditionHandle"
},
"'",
" 2>&1 >> /var/log/initial_user-data.log\n"
]
]
}
}
It looks like $CFNSTATUS is not being set to 0 (or an error), but rather is empty. I proved this by adding a line to echo $CFNSTATUS into a file in /tmp, and also to provide a 0 to the --exit-code argument in the call to /usr/bin/cfn-signal.
Once I made those changes, the server built.
Not sure why this would be so.
@edgreenberg Good catch. The reason for that bug was that the line that runs dmidecode doesn't have a trailing \n. So the line that looks like this
" - dmidecode 2>&1 >> /tmp/custom-output.txt",
should have looked like this
" - dmidecode 2>&1 >> /tmp/custom-output.txt\n",
I'm updating this template to yaml which will solve this problem.
@locomotif The updated template contains the regions you'd mentioned. The AMI mapping is generated with code that you can find here (so that it won't miss any regions) : https://gist.github.com/gene1wood/56e42097e0f0ac1aace14cbc41ee3e11#file-create_centos7_cloudformation_ami_mapping-py
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@josdirksen, thanks for catching that! I've fixed it above at 3812576afe34046def330757c99a632bd127ed54