It seems there is no option to assign the global IP to a reseller automatically.
When a reseller orders via WHMCS either the reseller account creation fails or the reseller is created without any IP.
In WHMCS, when you set the Reseller IP to sharedreseller, automatic provisioning after payment will fail.
If you try to create the account manually from WHMCS Client Profile, WHMCS reports the account was created but it does not create the account.
In WHMCS, when you set the Reseller IP to shared, automatic provisioning after payment will NOT fail.
If you try to create the account manually from WHMCS Client Profile, WHMCS creates the account.
But in both cases, the reseller was created without any IP. Because of this, the reseller cannot create any client accounts.
You have to manually assign the global IP to the reseller and then they can create client accounts.
The whole process needs to be automatic.
That is, the global IP needs to be assigned to the reseller automatically during account creation.
When a reseller orders via WHMCS either the reseller account creation fails or the reseller is created without any IP.
In WHMCS, when you set the Reseller IP to sharedreseller, automatic provisioning after payment will fail.
If you try to create the account manually from WHMCS Client Profile, WHMCS reports the account was created but it does not create the account.
In WHMCS, when you set the Reseller IP to shared, automatic provisioning after payment will NOT fail.
If you try to create the account manually from WHMCS Client Profile, WHMCS creates the account.
But in both cases, the reseller was created without any IP. Because of this, the reseller cannot create any client accounts.
You have to manually assign the global IP to the reseller and then they can create client accounts.
The whole process needs to be automatic.
That is, the global IP needs to be assigned to the reseller automatically during account creation.