You can set IP addresses allowed to Login to your admin portal in Settings→Security Settings → Admin Area Allowed IPs.
If you'd like to go further, and block unwanted IP addresses on web-server level, you can do so by updating nginx config files.
How to IP-limit admin-area access on nginx
1. SSH to your HostBill Enterprise server as root:
2. Create file /etc/nginx/hostbill_phpfpm, add following contents to it
3. Edit file:
Replace its contents with following:
- Make sure to change /admin to other folder name, if you have changed your admin folder
- Add each allowed IP / CIDR subnet in new "allow X.X.X.X" block
- Save changes
3. Reload webserver's config