stacker is a tool and library used to create & update multiple CloudFormation stacks. It was originally written at Remind and released to the open source community.
stacker StackTemplates are written in troposphere, though the purpose of most templates is to keep them as generic as possible and then use configuration (and CloudFormation Parameters/Outputs) to modify them.
At this point this is very much alpha software - it is still in heavy development, and interfaces/configuration/etc may/will likely/most definitely change :)
We've provided an example stack in conf/example.yaml that can be launched in your account. It creates 4 stacks:
- A VPC (including NAT hosts in each AZ)
- A bastion stack (for ssh'ing into other stacks on the VPC)
- A RDS stack (postgres)
- An autoscaling group stack
The size of most of these is m3.medium, but you can change that in the config if you'd like to play with something smaller. To launch the stacks, after installing stacker and loading your AWS API keys in your environment (AWS_ACCESS_KEY_ID & AWS_SECRET_ACCESS_KEY), call the following:
stacker -v -r us-east-1 -d example.com -p CidrBlock=10.128.0.0/16 conf/example.yaml
Here's the syntax help from the command:
# stacker -h
usage: stacker [-h] [-r REGION] [-m MAX_ZONES] [-v] [-d DOMAIN]
[-p PARAMETER=VALUE] [--prompt]
config
Launches AWS Cloudformation stacks from config.
positional arguments:
config The config file where stack configuration is located.
Must be in yaml format.
optional arguments:
-h, --help show this help message and exit
-r REGION, --region REGION
The AWS region to launch in. Default: us-east-1
-m MAX_ZONES, --max-zones MAX_ZONES
Gives you the ability to limit the # of zones that
resources will be launched in. If not given, then
resources will be launched in all available
availability zones.
-v, --verbose Increase output verbosity. May be specified up to
twice.
-d DOMAIN, --domain DOMAIN
The domain to run in. Gets converted into the
BaseDomain Parameter for use in stack templates.
-p PARAMETER=VALUE, --parameter PARAMETER=VALUE
Adds parameters from the command line that can be used
inside any of the stacks being built. Can be specified
more than once.
--prompt Drop to python prompt rather than kicking off build of
the stack.
As of now there is no option to tear down the stack in the tool (we plan to add it), so you'll need to tear the stacks it creates down manually. When doing so, it's important that you tear down all the stacks BUT the VPC stack first, since they all depend on the VPC stack. Once they are torn down, you can safely tear down the VPC stack. If you try deleting them all (including VPC) in one swoop, you'll see that VPC stack gets hung up while waiting for the others to tear down.