Trainer tools to create and prepare VMs for Docker workshops on AWS
Prerequisites
General Workflow
- fork/clone repo
- set required environment variables for AWS
- create your own setting file from
settings/example.yaml - run
./trainercommands to create instances, install docker, setup each users environment in node1, other management tasks - run
./trainer cardscommand to generate PDF for printing handouts of each users host IP's and login info
Clone/Fork the Repo, and Build the Tools Image
The Docker Compose file here is used to build a image with all the dependencies to run the ./trainer commands and optional tools. Each run of the script will check if you have those dependencies locally on your host, and will only use the container if you're missing a dependency.
$ git clone https://github.com/jpetazzo/orchestration-workshop.git
$ cd orchestration-workshop/prepare-vms
$ docker-compose build
Preparing to Run ./trainer
Required AWS Permissions/Info
- Initial assumptions are you're using a root account. If you'd like to use a IAM user, it will need
AmazonEC2FullAccessandIAMReadOnlyAccess. - Using a non-default VPC or Security Group isn't supported out of box yet, but until then you can customize the
trainer-cliscript. - These instances will assign the default VPC Security Group, which does not open any ports from Internet by default. So you'll need to add Inbound rules for
SSH | TCP | 22 | 0.0.0.0/0andCustom TCP Rule | TCP | 8000 - 8002 | 0.0.0.0/0, or run./trainer opensgwhich opens up all ports.
Required Environment Variables
AWS_ACCESS_KEY_IDAWS_SECRET_ACCESS_KEYAWS_DEFAULT_REGION
Update/copy settings/example.yaml
Then pass settings/YOUR_WORKSHOP_NAME-settings.yaml as an argument to trainer deploy, trainer cards, etc.
./trainer cards 2016-09-28-00-33-bret settings/orchestration.yaml
./trainer Usage
./trainer <command> [n-instances|tag] [settings/file.yaml]
Core commands:
start n Start n instances
list [TAG] If a tag is provided, list its VMs. Otherwise, list tags.
deploy TAG Deploy all instances with a given tag
pull-images TAG Pre-pull docker images. Run only after deploying.
stop TAG Stop and delete instances tagged TAG
Extras:
ips TAG List all IPs of instances with a given tag (updates ips.txt)
ids TAG/TOKEN List all instance IDs with a given tag
shell Get a shell in the trainer container
status TAG Print information about this tag and its VMs
tags List all tags (per-region)
retag TAG/TOKEN TAG Retag instances with a new tag
Beta:
ami Look up Amazon Machine Images
cards FILE Generate cards
opensg Modify AWS security groups
Summary of What ./trainer Does For You
- Used to manage bulk AWS instances for you without needing to use AWS cli or gui.
- Can manage multiple "tags" or groups of instances, which are tracked in
prepare-vms/tags/ - Can also create PDF/HTML for printing student info for instance IP's and login.
- The
./trainerscript can be executed directly. - It will run locally if all its dependencies are fulfilled; otherwise it will run in the Docker container you created with
docker-compose build(preparevms_prepare-vms). - During
startit will add your default local SSH key to all instances under theubuntuuser. - During
deployit will create thedockeruser with passwordtraining, which is printing on the cards for students. For now, this is hard coded.
Example Steps to Launch a Batch of Instances for a Workshop
- Export the environment variables needed by the AWS CLI (see Required Environment Variables above)
- Run
./trainer start NCreatesNEC2 instances- Your local SSH key will be synced to instances under
ubuntuuser - AWS instances will be created and tagged based on date, and IP's stored in
prepare-vms/tags/
- Your local SSH key will be synced to instances under
- Run
./trainer deploy TAG settings/somefile.yamlto runscripts/postprep.rcvia parallel-ssh- If it errors or times out, you should be able to rerun
- Requires good connection to run all the parallel SSH connections, up to 100 parallel (ProTip: create dedicated management instance in same AWS region where you run all these utils from)
- Run
./trainer pull-images TAGto pre-pull a bunch of Docker images to the instances - Run
./trainer cards TAG settings/somefile.yamlgenerates PDF/HTML files to print and cut and hand out to students - Have a great workshop
- Run
./trainer stop TAGto terminate instances.
Other Tools
Deploying your SSH key to all the machines
- Make sure that you have SSH keys loaded (
ssh-add -l). - Source
rc. - Run
pcopykey.
Installing extra packages
- Source
postprep.rc. (This will install a few extra packages, add entries to /etc/hosts, generate SSH keys, and deploy them on all hosts.)
Even More Details
Sync of SSH keys
When the start command is run, your local RSA SSH public key will be added to your AWS EC2 keychain.
To see which local key will be uploaded, run ssh-add -l | grep RSA.
Instance + tag creation
10 VMs will be started, with an automatically generated tag (timestamp + your username).
Your SSH key will be added to the authorized_keys of the ubuntu user.
Creation of ./$TAG/ directory and contents
Following the creation of the VMs, a text file will be created containing a list of their IPs.
This ips.txt file will be created in the $TAG/ directory and a symlink will be placed in the working directory of the script.
If you create new VMs, the symlinked file will be overwritten.
Deployment
Instances can be deployed manually using the deploy command:
$ ./trainer deploy TAG settings/somefile.yaml
The postprep.rc file will be copied via parallel-ssh to all of the VMs and executed.
Pre-pull images
$ ./trainer pull-images TAG
Generate cards
$ ./trainer cards TAG settings/somefile.yaml
List tags
$ ./trainer list
List VMs
$ ./trainer list TAG
This will print a human-friendly list containing some information about each instance.
Stop and destroy VMs
$ ./trainer stop TAG
ToDo
- Don't write to bash history in system() in postprep
- compose, etc version inconsistent (int vs str)