How To Check MD5sums On A Linux Iso Image (using linux)

usalug · Sep 22, 2005

How To Check MD5sums On A Linux Iso Image (using linux)
originally posted here: http://www.usalug.org/phpBB2/viewtopic.php?t=1215

At the command prompt cd to the directory containing the iso's

Type md5sum the_name_ofthe_iso.iso

give your computer a minute to figure it out........ and it will display a long number and that should match the md5sum that the download site gave.

If they don't..... you have a corrupted iso file and will need to download again. Checking your downloaded iso's is an important step that shouldn't be forgotten, as it will save you headaches later on........ not to mention lost time.

A good place to read more is here : http://www.linuxiso.org/viewdoc.php/verifyiso.html

And here is what the man pages say about md5sum

md5sum - compute and check MD5 message digest
SYNOPSIS
md5sum [OPTION] [FILE]...
md5sum [OPTION] --check [FILE]
DESCRIPTION

Print or check MD5 (128-bit) checksums. With no FILE, or when FILE is -, read standard input.

-b, --binary
read files in binary mode (default on DOS/Windows)
-c, --check
check MD5 sums against given list
-t, --text
read files in text mode (default)

The following two options are useful only when verifying checksums:

--status
don't output anything, status code shows success
-w, --warn
warn about improperly formated checksum lines
--help
display this help and exit
--version
output version information and exit

The sums are computed as described in RFC 1321. When checking, the input should be a former output of this program. The default mode is to print a line with checksum, a character indicating type (`*' for binary, ` ' for text), and name for each FILE.
AUTHOR
Written by Ulrich Drepper and Scott Miller.
REPORTING BUGS
Report bugs to <[email protected]>.
COPYRIGHT
Copyright � 2002 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
SEE ALSO
The full documentation for md5sum is maintained as a Texinfo manual. If the info and md5sum programs are properly installed at your site, the command

info md5sum

should give you access to the complete manual.

If you want/need to check the md5sums you download onto a M$ (ewww) machine....

http://www.md5summer.org/
http://www.pc-tools.net/win32/md5sums/
http://www.accuhash.com