After getting my blog running using Google Cloud Platform cloud launcher option with the Bitnami Ghost prebuilt image I noticed the URL in my browser shows the IP address of the VM instead of showing the domain name I expected to see. After some research I found this is a configuration parameter in the Ghost config file. Since this is a Bitnami deployment the config file is located here:

sudo nano /opt/bitnami/apps/ghost/htdocs/config.js

In the config you will find the IP address of your Google Cloud Platform instance in the config object under each type of deployment production, development, and testing.

config = {
    // ### Production
    // When running Ghost in the wild, use the production environment.
    // Configure your URL and mail settings here
    production: {
        url: 'http://1.2.3.4:80',
        mail: {},
        database: {
            client: 'sqlite3',
            connection: {
                filename: path.join(__dirname, '/content/data/ghost.db')
            },
            debug: false
        },

        server: {
            host: '127.0.0.1',
            port: '2368'
        }
    },

Change the url key in the config object to reflect your domain name instead of the IP address for your GCP VM instance.

config = {
    // ### Production
    // When running Ghost in the wild, use the production environment.
    // Configure your URL and mail settings here
    production: {
        url: 'http://braytonstafford.com',
        mail: {},
        database: {
            client: 'sqlite3',
            connection: {
                filename: path.join(__dirname, '/content/data/ghost.db')
            },
            debug: false
        },

        server: {
            host: '127.0.0.1',
            port: '2368'
        }
    },

After changing the config file to reflect your domain name just run the following command to reload the configuration:

sudo /opt/bitnami/ctlscript.sh restart

After the configuration is reloaded Ghost will recognize your domain as the base URL!