Chapter 1. Obtaining Red Hat Enterprise Linux

Procedure 1.1. Downloading Red Hat Enterprise Linux ISO Images

1. Visit the Customer Portal at https://access.redhat.com/home. If you are not logged in, click LOG IN on the right side of the page. Enter your account credentials when prompted.
2. Click DOWNLOADS at the top of the page.
3. Click Red Hat Enterprise Linux.
4. Ensure that you select the appropriate Product Variant, Version and Architecture for your installation target. By default, Red Hat Enterprise Linux Server and x86_64 are selected. If you are not sure which variant best suits your needs, see http://www.redhat.com/en/technologies/linux-platforms/enterprise-linux.
5. A list of available downloads is displayed; most notably, a minimal Boot ISO image and a full installation Binary DVD ISO image. The Boot ISO is a minimal boot image which only contains the installer and requires a source to install packages from (such as an HTTP or FTP server). The Binary DVD download contains both the installer and necessary packages, and therefore requires less setup.
   Additional images may be available, such as preconfigured virtual machine images, which are beyond the scope of this document.
6. Choose the image file that you want to use. There are several ways to download an ISO image from Red Hat Customer Portal:
   • Click its name to begin downloading it to your computer using your web browser.
   • Right-click the name and then click Copy Link Location or a similar menu item, the exact wording of which depends on the browser that you are using. This action copies the URL of the file to your clipboard, which allows you to use an alternative application to download the file to your computer. This approach is especially useful if your Internet connection is unstable: in that case, you browser may fail to download the whole file, and an attempt to resume the interrupted download process fails because the download link contains an authentication key which is only valid for a short time. Specialized applications such as curl can, however, be used to resume interrupted download attempts from the Customer Portal, which means that you need not download the whole file again and thus you save your time and bandwidth consumption.

     Procedure 1.2. Using curl to Download Installation Media

     1. Make sure the curl package is installed by running the following command as root:

        # yum install curl

        If your Linux distribution does not use yum, or if you do not use Linux at all, download the most appropriate software package from the curl website.
     2. Open a terminal window, enter a suitable directory, and type the following command:

        $ curl -o filename.iso 'copied_link_location'

        Replace filename.iso with the ISO image name as displayed in the Customer Portal, such as rhel-server-6.9-x86_64-dvd.iso. This is important because the download link in the Customer Portal contains extra characters which curl would otherwise use in the downloaded file name, too. Then, keep the single quotation mark in front of the next parameter, and replace copied_link_location with the link that you have copied from the Customer Portal.
        Note that in Linux, you can paste the content of the clipboard into the terminal window by middle-clicking anywhere in the window, or by pressing Shift+Insert. Finally, use another single quotation mark after the last parameter, and press Enter to run the command and start transferring the ISO image. The single quotation marks prevent the command line interpreter from misinterpreting any special characters that might be included in the download link.

        Example 1.1. Downloading an ISO image with curl

        The following is an example of a curl command line:

        $ curl -o rhel-server-6.9-x86_64-dvd.iso 'https://access.cdn.redhat.com//content/origin/files/sha256/85/85a...46c/rhel-server-6.9-x86_64-dvd.iso?_auth_=141...7bf'

        Note that the actual download link is much longer because it contains complicated identifiers.
     3. If your Internet connection does drop before the transfer is complete, refresh the download page in the Customer Portal; log in again if necessary. Copy the new download link, use the same basic curl command line parameters as earlier but be sure to use the new download link, and add -C - to instruct curl to automatically determine where it should continue based on the size of the already downloaded file.

        Example 1.2. Resuming an interrupted download attempt

        The following is an example of a curl command line that you use if you have only partially downloaded the ISO image of your choice:

        $ curl -o rhel-server-6.9-x86_64-dvd.iso 'https://access.cdn.redhat.com//content/origin/files/sha256/85/85a...46c/rhel-server-6.9-x86_64-dvd.iso?_auth_=141...963' -C -

7. Optionally, you can use a checksum utility such as sha256sum to verify the integrity of the image file after the download finishes. All downloads on the Download Red Hat Enterprise Linux page are provided with their checksums for reference:

   $ sha256sum rhel-server-6.9-x86_64-dvd.iso
   85a...46c rhel-server-6.9-x86_64-dvd.iso

   Similar tools are available for Microsoft Windows and Mac OS X. You can also use the installation program to verify the media when starting the installation; see Section 28.6.1, “Verifying Boot Media” for details.