How To Add Parked Domains In Bulk From The Command Line?

Introduction

You can use the WHMAPI1 API call create_parked_domain_for_user for this purpose. This API call works from the command line as well. You can refer to the following links for more information on this particular API call and how to use API calls from the command line in general:

create_parked_domain_for_user

Using cPanel's APIs From The Command-Line

Procedure

Let's assume you want to add any number of parked domains to the already existing virtual host domain.tld for the user cpuser.

You need to first create a file (use nano or vi/vim for this purpose), let's call it YOUR_FILE and add all the domains to the file, each on a separate line. The content of the file should be similar to this:

cat YOUR_FILE

test1.domain.tld
test2.domain.tld
test3.domani.tld
test4.domain.tld
test5.domain.tld
test6.domain.tld
.......

Then use this simple command to loop over the domains in the file adding them one by one as aliases (AKA parked domain) to the domain.tldvirtual host, using the aforementioned API call. Of course here you need to replace the YOUR_FILE in this command with the absolute path of the file that you've created and also domain.tld and cpuser need to be replaced with the appropriate values for your case: 

for domain in `cat YOUR_FILE`;do whmapi1 create_parked_domain_for_user domain=$domain username=cpuser web_vhost_domain=domain.tld;done

However, please bear in mind that this is only for demonstration purposes and it's always recommended that you refer to the links provided above and create your own command to completely tailor the command to your specific needs.