  We study the entropy evolution of black holes in Lovelock gravity by
formulating a thermodynamic generalization of null Raychaudhuri equation. We
show that the similarity between the expressions of entropy change of the black
hole horizon due to perturbation and that of a fluid, which is out of
equilibrium, transcends beyond general relativity to the Lovelock class of
theories. Exploiting this analogy we find that the shear and bulk viscosities
for the black holes in Lovelock theories exactly match with those obtained in
the membrane paradigm and also from holographic considerations.
