I did the simulation with a square lattice of the dielectric pillar and got the bandstructure like this. I could not interpret anything from this. 

I used the example file "Planer3D_hex" and did the modification. Even I did not understand the resulting band structure it right or wrong. 

What I observed in the simulation of the example file, in simulation status, the status is showing 1, even with a large simulation time. Is it because of Bloch BC? 

What I found in the literature is that Photonic bandstructure can be generated for both TE and TM modes like this, 

Band diagram and photonic band gap for TM and TE waves [13] | Download  Scientific Diagram

How to do that?