While there are many cloud providers (e.g.: AWS, Microsoft Azure, DigitalOcean, etc.), today we are going to use Google Cloud. By signing up here with your university email (${YOUR_ID}@stud.acs.upb.ro most likely), you will get $50 in credits to play around with their infrastructure up until the 10^th of April. In case you aren't forwarding your UPB emails to/from your main account via IMAP/POP, you can access them in outlook.

Normally, cloud provides give you the option to access a web dashboard. Using this is fine for starting up one virtual machine, or checking your billing settings. However, if you want to do some automation work, you will want to utilize the gcloud SDK. By following the instructions here, you should be able to install the gcloud CLI application. Finally, you will be asked to run:

# create default configuration for usage with gcloud
$ gcloud init

CLI tools like ip and gcloud work based on a more modern paradigm. If older programs mainly use flags (i.e.: --this, -t) to specify what functionality should be invoked at runtime, these use commands and subcommands for a more intuitive classification. For example:

# <tool_name> <subject> <action>
$ gcloud projects list              
PROJECT_ID      NAME            PROJECT_NUMBER
lab-radumantu   lab-radumantu   1234567890

$ gcloud compute networks <TAB>
create                   get-effective-firewalls  subnets                                         
delete                   list                     update                                          
describe                 peerings                 vpc-access 

Note that sometimes, the feature that you want to access is in fact hidden behind the alpha or beta commands. These commands indicate that the development version of regular commands should be used in stead.

# try to list your configured billing accounts
$ gcloud billing accounts list
ERROR: (gcloud.billing) Invalid choice: 'accounts'.
This command is available in one or more alternate release tracks.  Try:
  gcloud alpha billing accounts
  gcloud beta billing accounts
 
# now try the same thing with the alpha variant of the command
$ gcloud alpha billing accounts list
ACCOUNT_ID            NAME                           OPEN   MASTER_ACCOUNT_ID
XXXXXX-XXXXXX-XXXXXX  Billing Account for Education  True

Now knowing your project ID and your billing account ID, it's time to link the two. This way, when you request resource allocation from the gcloud compute engine, Google will know to use the $50 credit account (charges are usually made at the end of the month). While there's also an alpha version of the following command, we'll be using the recommended beta variant:

# link billing account to gcloud project
$ gcloud beta billing projects link ${PROJECT_ID} --billing-account ${BILLING_ACC_ID}

Before we proceed to actually starting instances in different locations, here's one final config that we should do.

# set default project id
$ gcloud config set core/project ${PROJECT_ID}
 
# check that new value was saved
$ gcloud config list
[core]
...
project = ${PROJECT_ID}

Setting the core/project propriety is optional. However, not setting it would have meant that every time you invoked a gcloud compute command, you would have been required to also pass a --project=${PROJECT_ID} flag. Which is annoying…