How can I use mpi with more computers?

I have there computers(node1,nodes2 and node3),which I used nfs to shared the files of node1 to node2 and node3.I can use two computers to simulate with node1 and and node2. But I cannot use node2 and node3 to simulate.,that using node1,node2 and node3 is like it.

The error is:(it never ends)

k-effective (Track-length) = 1.13892 +/- 0.00400
k-effective (Absorption) = 1.14686 +/- 0.00342
Combined k-effective = 1.14444 +/- 0.00281
Leakage Fraction = 0.00000 +/- 0.00000

Creating state point openmc_simulation_n1.h5…
mca_fbtl_posix_preadv: error in (p)readv:Input/output error