WHMCS module for resellers of remote-backups.com. Lets hosting providers sell managed backup storage to their customers through automatic provisioning, usage tracking, and billing.

Developed by Nerdscave Hosting

• Automatic datastore creation on order, deletion on termination
• Resize on upgrades/downgrades via the API

• Prorated billing based on the API's rescale-log (tracks every resize event)
• Configurable pricing per 1000 GB with min/max size limits
• Weighted-average billing calculations using actual resize timestamps

• All datastores listed with status, usage, and links to WHMCS services
• Rescale log view (from, to, auto/manual, timestamp)
• Connection test button

• Connection credentials with copy-to-clipboard and password reveal
• Collapsible advanced info (IPs, fingerprint)
• Storage usage and transfer rate graphs (Chart.js)
• Settings tab: resize datastore, autoscaling config, bandwidth limit
• Prune settings tab: retention limits (keep-last, hourly, daily, weekly, monthly, yearly) and schedule (days + hours). Clearing a field sends 0 to the API, which removes the limit without forwarding to PBS

Two components: an addon module for admin/config and a server module for provisioning and the client area.

Handles config and admin. On activation it creates a database table for datastore mapping. Admins set their API token, price per 1000 GB, and size limits. The dashboard lists all datastores with current size, usage, and links to WHMCS services.

Handles provisioning. On order, WHMCS calls CreateAccount which creates a datastore via the API and stores the mapping. Termination deletes the datastore. Upgrades/downgrades resize it.

On invoice creation, the module fetches the rescale-log from the API (GET /reseller/datastore/{id}/rescale-log) and calculates prorated cost:

1. Determine billing period - Based on the service's billing cycle (monthly, quarterly, etc.)
2. Fetch rescale-log - Get all resize events from the API covering the billing period
3. Build timeline - Reconstruct the size at each point using the from/to fields and createdAt timestamps
4. Calculate weighted average - Multiply each size by its duration in hours
5. Apply pricing - Use the configured price per 1000 GB

Formula:

Average GB = (Σ Size_GB × Hours_at_that_size) / Total_hours_in_period
Monthly Cost = Average_GB × (Price_per_1000GB / 1000)

Given this rescale-log for a monthly billing cycle:

Calculation:

• 500 GB × 11.5 hours = 5,750 GB-hours
• 600 GB × 732.5 hours = 439,500 GB-hours (rest of month)
• Total = 445,250 GB-hours
• Period = 744 hours (31 days in January)
• Average = 598.45 GB

At €10/1000GB/month: 598.45 GB × €0.01 = €5.98

The invoice description will show: "Usage-based billing: 598.45 GB average over 744 hours"

• WHMCS 8.0 or higher
• PHP 8.0 or higher with cURL extension
• A reseller account at remote-backups.com with API access

Copy the module directories to your WHMCS installation:

modules/addons/remotebackups/    -> /path/to/whmcs/modules/addons/remotebackups/
modules/servers/remotebackups/   -> /path/to/whmcs/modules/servers/remotebackups/

Go to Setup, then Addon Modules. Find Remote Backups in the list and click Activate. Click Configure and enter:

• Your API token from remote-backups.com
• The monthly price per 1000 GB in your default currency
• Minimum datastore size in GB (customers cannot order smaller)
• Maximum datastore size in GB (customers cannot order larger)

Go to Setup, then Products/Services, then Products/Services. Create a new product and under Module Settings, select Remote Backups. Configure:

• Datastore Size (GB): The size of the datastore for this product
• Name Prefix: A prefix for datastore names, for example "backup"

The module will create datastores named like "backup-client123-service456" to ensure uniqueness.

Base URL: https://api.remote-backups.com (reseller API, no /v1 prefix).

Sizes go to the API in GB. The API returns bytes, which the module converts back.

Size constraints: 500-10000 GB, increments of 100 GB.

Created on activation:

mod_remotebackups_datastores — maps datastore IDs to WHMCS service IDs, stores current size.

Check your API token. Go to Addons > Remote Backups > Test Connection.

Make sure the module files are in the right place. The server module at /modules/servers/remotebackups/ needs to be able to load the addon module at /modules/addons/remotebackups/.

Check the module log under Utilities > Logs > Module Log. All API requests and responses are logged there.

• Billing now uses the API's rescale-log endpoint instead of local hourly polling
• Removed cron.php (no more hourly cron needed)
• Removed mod_remotebackups_size_history database table
• Admin "Usage History" replaced with "Rescale Log" showing data from the API

• Initial release

GPL-3.0-or-later

Copyright 2026 Moritz Mantel / Nerdscave Hosting

• Nerdscave Hosting
• remote-backups.com
• API Reference
• API Swagger UI
• remote-backups.com Documentation