In some examples, a computing system can include an exterior enclosure for the computing system, an electrical component within the enclosure, an interior cooling line within the enclosure to circulate coolant past the electrical component to remove heat generated by the electrical component, and an inlet coolant line port through the exterior enclosure to receive an inlet coolant line. The inlet coolant line port can, for example, include a sensor to detect tampering with an interior of the inlet coolant line.