Checking ISOs

From Mandrivausers Wiki

Note: This part of the Wiki is largely derived from the Sidux manual pages which are All content is © 2006 by the sidux Foundation, Inc. and released under GNU/FDL.

Everytime you download an ISO the same directory should include a file called something like MD5.

This is a checksum for a file and is used to check the integrity of files. The current MD5-Sum of the file can be compared with a known checksum. This way you can validate if a file has been changed or damaged; this is advisible for files downloaded from the internet.

If the md5-sum of the downloaded file corresponds to the one in the md5-file, you can be sure that the file was downloaded correctly. Under Linux you get the checksum with:(it takes a moment to calculate)

$ md5sum file_to_check

The sum will be written in the konsole. With md5summer (486 kb) the md5-sum can also be validated in Windows.

The ISO-Images of all major distro's are always offered with a md5-checksum file and should always be validated before burning. This guarantees that if problems occur later its not because of a faulty download or currupt file. $ md5sum -c downloaded_file.iso.md5

If they don't match, you will get an error:

"downloaded_file.iso: Error md5sum: Warning: calculated checksum does not match!"

If the downloaded file is correct, the program ends without a message.

You can also in Linux use for instance K3B, more details for this are available under How to Burn a CD.