Red Hat Knowledgebase

An md5sum is the output of an algorithm generated from the data contained in the file. Even minor changes in the file will cause the md5sum to be drastically different. For more information on how an md5sum works the Wikipedia contains an in-depth article.

When downloading the ISO files from the Red Hat Network (RHN) you can use an Open Source tool called winmd5sum to generate an md5sum from the downloaded file.

The winmd5sum application can be downloaded from the Solid Blue website at http://winmd5sum.solidblue.biz.

After downloading winmd5sum, run it by double clicking on the icon. Drag and drop the ISO file into the file name dialog box and click the "Calculate" button. In a few moments an md5sum will be generated. On an older computer this operation may take some time.

On the Red Hat Network "Easy ISO" link where the ISO files were downloaded, beside each ISO file should be a string of characters. Copy the MD5Sum beside the relevant ISO file and paste it into the "Compare" text entry box.

If the md5sum file does not match, you will need to download the ISO file from the Red Hat Network again.