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I am trying to use the MPI capabilities of john 1.7.9 and am testing with a simple 4-char password on a single 8-core server machine. I noticed that after success, the process that cracked the password exits, while the rest remain running. Is this a known issue, or a new bug? Also, is there a workaround (apart from monitoring the time of each process and looking for differences, which is not really conclusive).

Details:

mpiexec --version
 mpiexec (OpenRTE) 1.4.3
...
mpiexec -n 8 -host localhost ./run/john temp --format=raw-md5
...
mpiexec -n 8 -host localhost killall -s HUP john && mpiexec -n 8 -host localhost ./john --status
 0: guesses: 0 time: 0:00:00:07 0.00% (3) c/s: 4424K
 3: guesses: 0 time: 0:00:01:35 0.00% (3) c/s: 7985K
 7: guesses: 0 time: 0:00:01:34 0.00% (3) c/s: 7190K
 4: guesses: 0 time: 0:00:01:35 0.00% (3) c/s: 6643K
 6: guesses: 0 time: 0:00:01:35 0.00% (3) c/s: 7319K
 1: guesses: 0 time: 0:00:01:34 0.00% (3) c/s: 9367K
 2: guesses: 0 time: 0:00:01:34 0.00% (3) c/s: 6774K
 5: guesses: 0 time: 0:00:01:35 0.00% (3) c/s: 6740K
 SUM: guesses: 0 time: 0:00:01:35 0.00% (3) c/s: 59635K avg 7454K

Notice process 0's running time and how it still reports 0 guesses. Running john --status shows the following:

./run/john --show temp --format=raw-md5
?:asdq

1 password hash cracked, 0 left
share|improve this question

If you use OpenMPI instead of mpich2, the SIGHUP signal doesn't get passed to john. It is necessary to send a SIGUSR1 instead.

share|improve this answer
    
Your answer would be even more helpful, and better suited for future reference, if you linked some documentation about this behaviour. – kopischke Jan 28 '13 at 10:55
    
This answer is not related to the question, as the provided output shows that the SIGHUP does get passed to john. – Shade Jan 28 '13 at 15:20

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