  We describe the implementation of the shearingbox approach into the
Godunov-type central-upwind/constraint-transport magnetohydrodynamics code
NIRVANA. This will allow for applications which require sheared-periodic
boundary conditions as typically used in local Cartesian simulations of
differentially rotating systems. We present the algorithm in detail and discuss
necessary modifications in the numerical fluxes in order to preserve conserved
quantities and to fulfill other analytical constraints as good as seem feasible
within the numerical scheme. We check the source terms which come with the
shearingbox formulation by investigating the conservation of the epicyclic mode
energy. We also perform more realistic simulations of the magneto-rotational
instability with initial zero-net-flux vertical magnetic field and compare the
obtained stresses and energetics with previous non-conservative results
exploring the same parameter regime.
