grounding a panel
I have a service pole with a meter and external panel that is 250' from my house and 100' from both my garage and a small cabin. The service panel feeds 100 amps to the house and 100 amps each to the sub panel in the garage and to the new subpanel in the cabin.
The phone company tells me that I need a ground (two 6' copper rods with copper wire) at the cabin to ground the subpanel there and to ground their NIB. The service panel is grounded and is about 10' from their phone pole. Can they ground the phone line to the service pole ground and not at the cabin?
The subpanel in the garage is not grounded. I am not sure about the house, as it is 70 years old and I cannot see any copper poles into the ground.
I am ready to close and tape the sheetrock around the panel in the cabin so I need to know if it has to be grounded there. No appliances int he cabin, just phone, computers, lights, fan...