A simple cloud (cluster of docker containers) management tool written in python. It provides, manual scaling, auto scaling and fault-tolerance.

Steps

1. make sure you create a python3 virtualenv and activate it
2. do pip install -r requirements
3. run python SimpleCluster/Manager.py
4. make sure you have a local etcd server running on port 2379, if its running on a different port, set it in the SimpleCluster/StateStorage.py file

Commands

1. help, will list all the commands available
2. ps, will list all of the apps that are running
3. start , will start a new app
4. list , will list the containers for that app
5. stop , will stop the app
6. scaleup , will scale the app to the specified number
7. scaledown , will scale down the app to the specified number
8. start-autoscaling will start autoscaling
9. stop-autoscaling will stop autoscaling
10. if anything goes wrong there is a "clean-slate" command that will remove everything

Parallel Threads

We have two parallel threads running apart from the main one

1. auto-scaling thread, that is started or stop with the autoscaling command
2. house-cleaning thread, this is started as soon as the manager starts. This monitors the number of workers that should be running for a particular application. This threa is responsible for respawning dead workers. The check is made every 10 secs.