At Munich Airport, smoking is only allowed outside in front of the entrance and exit doors, at the outdoor area of the Munich Airport Center and in designated smoking areas.
You can find smoking lounges in Terminal 1 (Modules A, B, C, D and F) and Terminal 2 (Gates G, H, K, L) in the non-public area behind security check.
You can find maps here but they’re difficult to follow. I’ll try to add them here shortly.