Network parameters of VPS resource set to "Use IP pools, assigned to hardware node".
Despite that IP pool assigned to hardware node was not used for allocating IP for VPS that was being provisioned that hardware node.
System assigned the IP address from the IP pool attached to the service template.
The settings of service template prevail over resource settings. To use the settings defined in activation parameters of resource ("Use IP pools, assigned to hardware node"), set the parameter "IP pool identifier with global routed IP addresses" to 'auto' on Service Templates > > Parameters tab