While we refer to the process as "adding a Subdomain", the actual method of doing this is called "adding an A record".
Adding an A record with 1&1 IONOS
- Log in to your 1&1 IONOS account.
- Click Domains & SSL.
- Find the domain that you want to configure
- Under its cog settings on the right, select DNS
- Click Add record
- Click on A (Assign an IPv4 address for your domain or subdomain)and enter the following information:
- In the Host Name box enter: booking - this is your chosen subdomain such as "book" or "reservations" etc.
- In the Points to box, enter 220.127.116.11 - this points your subdomain to the BoothBook server
- Leave the TTL set to 1 hour.
- Click Save.
It may take up to 48 hours for your custom subdomain to set up properly, you can check on its progress by entering your subdomain eg. booking.mybusiness.com into this website: https://www.whatsmydns.net and click Search. If correct, you will start to see green ticks appearing soon after you've created your A Record, like below. Once every row has a green tick, and is pointing at only 18.104.22.168 your subdomain is ready for us to create your BoothBook system.