PCF - Cloud Foundry Overview - Deployment

how do you deploy an application? 

Applications can be deployed using '$ cf push' command. With this command CF performs the following tasks:

1. Uploads and store the app files
2. Examines and stores app metadata
3. Creates a 'droplet' i.e. CF unit of execution, for the app
4. Selects an appropriate Diego cell to run the droplet
5. Starts the app

If app is using the services i.e. db, messaging or email server, then app will not be fully functional until services are provisioned and binded to the app.

What are the activities involved?

Step 1: Deployment preparation

1. Ensure application is cloud-ready. CF behaviors related to file storage, http sessions and port usage may require modifications.

2. Ensure all app resources are uploaded

3. Extraneous files and artifacts are excluded from the app.

4. An instance of every service that app needs has been created

5. Ensure that CF supports the type of app you are deploying.

Step 2: Credentials and Target

1. API endpoint of of instance

2. Org and Space where app have to be deployed

2. Username and password

Step 3: Configure domains

1. CF directs the requests to an app using a route, which is a url made up of a host and a domain

2. Name of an app is the default host for that app.

3. Every app is deployed to an app space that belongs to a domain. 4. Every cf space has a default domain defined.

5. Custom domain can be defined while deploying, provided that the domain is registered and mapped to the organization which contains the target app space.

6. URL for the app should be unique in CF

7. use -n to assign a different host name for the app

8. Use --random-route to create a URL that includes the app name and random keywords

Step 4: Determine deployment options

1. Name of the app

2. Instances of app

3. Memory limit - maximum amount of memory required to run the app.

4. Start command

5. Subdomain (host) and Domain

6. Services

7. Define deployment options on command line or in a manifest file or both.

8. Configure pre-runtime hooks (except Java buildpack) - Pre-runtime looks are app specific initialization tasks, such as setting env variables. hooks are defined in .profile files in apps root directory. CF executes them after buildpack and immediately before each instance of app start.

Step 5: Push the app

1. run the command 'cf push APP-NAME'

Step 6: Configure Service Connections (optional)
1. Configure you app with Service url's and credentials

Step 5: Troubleshoot deployment problems