I discuss N = 4 SYM theories with su(N) gauge algebra, classified by the quotient discrete groups and line (and surface) operators, via the holographic dual description. The one-form symmetries and the line operator spectrum of the different theories are realized by the different boundary conditions on the NSNS and RR 2-forms in type IIB string theory. The topics include the holographic realization of the SL(2,Z) duality orbit, the mixed ’t Hooft anomaly involving the one-form and CP symmetries, and the interfaces between vacua with different values of the theta parameter. This talk is based on the work-in-progress in collaboration with Oren Bergman.