Welcome to the MacNN Forums.

JohnCoffee · Nov 16, 2003, 10:41 AM

I want to test the integrity of a file by doin a md5 checksum comparison on two computers. but the md5 checksum returned by the "openssl md5" command differs all the time on the same computer !
This happens on a 1.43 GB file only. Another file with a50MB is fine - always the same number..

Here the terminal windows output for the 1.5GB file:
[JCs-Computer:~/desktop] johncoff% openssl md5 file.sit
MD5(file.sit)=82f9ce5fb6e4fa26d7259e907674fda7
[JCs-Computer:~/desktop] johncoff% openssl md5 file.sit
MD5(file.sit)=a0dde91cdb1c570ba152ab51964e2cf8

and here for the 50MB file:
[JCs-Computer:~/desktop] johncoff% openssl md5 file1.sit
MD5(file1.sit)= 508086a906e9b713be4395d399eef2ca
[JCs-Computer:~/desktop] johncoff% openssl md5 file1.sit
MD5(file1.sit)= 508086a906e9b713be4395d399eef2ca

any suggestion ??

Arkham_c · Nov 16, 2003, 01:12 PM

I don't have any suggesions, other than to say that it should not do that.

I tried it on my system on several different files and did not experience that. The largest file I had available was 650MB, but it was consistent:

Code:
[arkham@MetalGear ~/Downloads] openssl md5 armyops190-mac.dmg.sitx         
MD5(armyops190-mac.dmg.sitx)= fa77b8b1ec09926db8a78043b80d5b4a
[arkham@MetalGear ~/Downloads] openssl md5 armyops190-mac.dmg.sitx
MD5(armyops190-mac.dmg.sitx)= fa77b8b1ec09926db8a78043b80d5b4a

proton · Nov 16, 2003, 05:28 PM

Just tried on a 4.36GB DVD image file:

% openssl dvd.dmg
MD5(bigfile)= b88031372b287322ac85b91637dd8473
% openssl dvd.dmg
MD5(bigfile)= b88031372b287322ac85b91637dd8473
% openssl dvd.dmg
MD5(bigfile)= b88031372b287322ac85b91637dd8473

Are you sure the file you're trying on wasn't being modified in some way?

- proton

JohnCoffee · Nov 18, 2003, 12:54 AM

Originally posted by proton:
Just tried on a 4.36GB DVD image file:

% openssl dvd.dmg
MD5(bigfile)= b88031372b287322ac85b91637dd8473
% openssl dvd.dmg
MD5(bigfile)= b88031372b287322ac85b91637dd8473
% openssl dvd.dmg
MD5(bigfile)= b88031372b287322ac85b91637dd8473

Are you sure the file you're trying on wasn't being modified in some way?

- proton

thanks for your help.
I locked the files before doin the test...hmm...tried again with a 390MB file.
What I found out is, that when I repeat a test, I get the same number, but when switching between 2 files, I get different figures.
here:

sitx.1)=97084dd1e0904aab75cd1ef5411c6789
sitx.1)=97084dd1e0904aab75cd1ef5411c6789
sitx.2)=0852d1e5f56174a4919391e27f7783e1
sitx.1)=b27f1175eedb345c6e980002b5e45e5f

any guess?
I'm on a DUAL G4 here....maybe it would be worth trying to do this with one CPU only?

any other thoughts?

proton · Nov 18, 2003, 02:14 AM

Still doesn't happen for me:

% openssl md5 dvd.dmg
MD5(dvd.dmg)= b88031372b287322ac85b91637dd8473
% openssl md5 dvd.dmg
MD5(dvd.dmg)= b88031372b287322ac85b91637dd8473
% openssl md5 cd.dmg
MD5(cd.dmg)= 3b6619cffb5f96e1acfa578badae372f
% openssl md5 dvd.dmg
MD5(dvd.dmg)= b88031372b287322ac85b91637dd8473

On a side note, geez that takes a while to MD5 the DVD image, even on my G5

- proton

JohnCoffee · Nov 18, 2003, 03:05 PM

Originally posted by proton:
Still doesn't happen for me:

% openssl md5 dvd.dmg
MD5(dvd.dmg)= b88031372b287322ac85b91637dd8473
% openssl md5 dvd.dmg
MD5(dvd.dmg)= b88031372b287322ac85b91637dd8473
% openssl md5 cd.dmg
MD5(cd.dmg)= 3b6619cffb5f96e1acfa578badae372f
% openssl md5 dvd.dmg
MD5(dvd.dmg)= b88031372b287322ac85b91637dd8473

On a side note, geez that takes a while to MD5 the DVD image, even on my G5

- proton

Thanks Proton. I still have the problem. Interestingly not for a file with 249Mb. For a 390MB file, the problem exists:

Have 8 files here: sitx.1 - sitx.8 and repeated the test 3 times. sometimes it matches on some tests. sometimes not. file 8 tests fine all 3 times as the only one. (249MB)

SHA1(.sitx.1)= 6202b26b4abcd1e1b140906f5a6141b4ed68ed35
SHA1(.sitx.2)= 6bc3fa4750e3fe17f9c0509b8a47006080ccb2f4
SHA1(.sitx.3)= bf16b899ac504584f5b780a9d4be9e5a8205f41a
SHA1(.sitx.4)= bd8ef93b8470ff478dcc85682033b1da2706877e
SHA1(.sitx.5)= f5b08f377d255fc96e1e1f93b529d6df57576f82
SHA1(.sitx.6)= 0ba358be0609585b524b045351127f828f2bcc1e
SHA1(.sitx.7)= 528f64bcd8dc2fac3072c42b28fd11275606f7f9
SHA1(.sitx.8)= 9122e5f3ad3b17d7a6c45647fb097499dd26f8dc
SHA1(.sitx.1)= 97ebedd8c2711b688370b752a303b0c0eb7f67ce
SHA1(.sitx.2)= 6f76812153960c4b412664921afe9835cfb08e66
SHA1(.sitx.3)= bf16b899ac504584f5b780a9d4be9e5a8205f41a
SHA1(.sitx.4)= c0ae8a0d3bfe0fbee345a6f9e123b9049b5611cb
SHA1(.sitx.5)= 76d70396d4099034807af5fde639cefdff68572b
SHA1(.sitx.6)= 0ba358be0609585b524b045351127f828f2bcc1e
SHA1(.sitx.7)= 9c8580373977a308f404374a65fe485b7d00dc67
SHA1(.sitx.8)= 9122e5f3ad3b17d7a6c45647fb097499dd26f8dc
SHA1(.sitx.1)= b5ed1f10e37dd769e7af3c1b1ac65c7f6113d7ac
SHA1(.sitx.2)= 6bc3fa4750e3fe17f9c0509b8a47006080ccb2f4
SHA1(.sitx.3)= e845ce3a5b7bb555eab884aba6a228d2b7d91d36
SHA1(.sitx.4)= c0ae8a0d3bfe0fbee345a6f9e123b9049b5611cb
SHA1(.sitx.5)= f5b08f377d255fc96e1e1f93b529d6df57576f82
SHA1(.sitx.6)= 2a62c52a1e43a67463f1929f2a027f094724afc4
SHA1(.sitx.7)= 9c8580373977a308f404374a65fe485b7d00dc67
SHA1(.sitx.8)= 9122e5f3ad3b17d7a6c45647fb097499dd26f8dc

any other hint?

JohnCoffee · Nov 20, 2003, 02:35 PM

Problem solved.....

Memory 512MB was faulty. ....

regards

John

diamondsw · Nov 20, 2003, 04:15 PM

Originally posted by JohnCoffee:
Problem solved.....

Memory 512MB was faulty. ....

regards

John

Rather an interesting way to determine that. I'll keep tht in mind as a simple troubleshooting method.

proton · Nov 20, 2003, 07:21 PM

Originally posted by JohnCoffee:
Problem solved.....

Memory 512MB was faulty. ....

regards

John

Guess that means my RAM is in good nick

Great to see you found the problem.

- proton