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We scrutinize the red dwarf component in the eclipsing binary system V471 Tauin order to unravel relations between different activity layers from thestellar surface through the chromosphere up to the corona. We aim at studyinghow the magnetic dynamo in the late-type component is affected by the closewhite dwarf companion. We use space photometry, high resolution spectroscopyand X-ray observations from different space instruments to explore the maincharacteristics of magnetic activity. From K2 photomery we find that 5-10 percent of the apparent surface of the red dwarf is covered by cool starspots.From seasonal photometric period changes we estimate a weak differentialrotation. From the flare activity we derive a cumulative flare frequencydiagram which suggests that frequent flaring could have a significant role inheating the corona. Using high resolution spectroscopy we reconstruct fourDoppler images for different epochs which reveal an active longitude, that is,a permanent dominant spot facing the white dwarf. From short term changes inthe consecutive Doppler images we derive a weak solar-type surface differentialrotation with 0.0026 shear coefficient, similar to that provided by photometry.The long-term evolution of X-ray luminosity reveals a possible activity cyclelength of 12.7 ys, traces of which were discovered also in the H$\alpha$spectra. We conclude that the magnetic activity of the red dwarf component inV471 Tau is strongly influenced by the close white dwarf companion. We confirmthe presence of a permanent dominant spot (active longitude) on the red dwarffacing the white dwarf. The weak differential rotation of the red dwarf is verylikely the result of tidal confinement by the companion. We find that theperiodic appearance of the inter-binary H$\alpha$ emission from the vicinity ofthe inner Lagrangian point is correlated with the activity cycle.

A confined dynamo: magnetic activity of the K-dwarf component in the pre-cataclysmic binary system V471 Tauri