If I use: john --incremental UNSHADOWEDFILEthen I can see it uses only 1 CPU. How can I set john to use several CPU's for finding the weak passwords? (need to find weak ones faster because of an audit)
How to run john parallel on several CPU's?
password
Basically you have to make sure that you use a recent John version that has OpenMP support enabled.If you compile it yourself you have to explicitly enable OpenMP support in the makefile (and verify that needed dependencies are available - e.g. a GCC >= 4.2).OpenMP support is not necessarily available for all hash methods, and the community edition (-jumbo) supports more than the official one.With the resulting binary you can verify if it has OpenMP via calling ldd on it - it should display some mp-related libraries. Also you can specify via the environment variable OMP_NUM_THREADS the number of cores a OpenMP program should use - if it is unset the default (on Linux) should be: all cores.See also the notes on OpenMP in John's Wiki.