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I am a linux noob trying to optimize John the Ripper for a security class. I am trying to use both processors to run John by using the mpirun program as suggested in this tutorial. I installed mpirun, but when I run this command, I get the following error:

# sudo mpirun -np2 /usr/share/john --test=10 
/usr/bin/mpirun: 1: eval: usr/share/john: Permission denied.

Why am I getting this error and how can I run John with two processors using mpirun? I am running Ubuntu 12.10 on a VMware Fusion machine on a Mac with an Intel Core i5

share|improve this question
You can also compile John with OpenMP, which speeds up certain hash types. The jumbo patch includes OpenMP support and many more optimizations and hash types: github.com/magnumripper/JohnTheRipper – bonsaiviking Feb 4 '13 at 15:15

/usr/share/john is probably not the path to the binary, but to the folder containing application specific data.


sudo mpirun -np 2 /usr/sbin/john --test=10 


share|improve this answer
Thanks. When I ran that command I got an error saying john.ini is missing. I copied the john.ini file. Now when I run the command that you suggest from root, I get: Unrecognized argument -np2 ignored. Any suggestions? – bernie2436 Feb 4 '13 at 13:47
There is a space missing after -np. I updated my answer. – jofel Feb 4 '13 at 14:29
And you can call john as normal user, you do not need sudo. – jofel Feb 4 '13 at 14:33

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