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Chapter 12. Preparing for Installation
12.1. Preparing for a Network Installation
The eHEA module fails to initialize if 16 GB huge pages are assigned to a system or partition and the kernel command line does not contain the huge page parameters. Therefore, when you perform a network installation through an IBM eHEA ethernet adapter, you cannot assign huge pages to the system or partition during the installation. Large pages should work.
Make sure no installation DVD (or any other type of DVD or CD) is in your system's CD or DVD drive if you are performing a network-based installation. Having a DVD or CD in the drive might cause unexpected errors.
Ensure that you have boot media available on CD, DVD, or a USB storage device such as a flash drive.
The Red Hat Enterprise Linux installation medium must be available for either a network installation (via NFS, FTP, or HTTP) or installation via local storage. Use the following steps if you are performing an NFS, FTP, or HTTP installation.
The NFS, FTP, or HTTP server to be used for installation over the network must be a separate, network-accessible server. It must provide the complete contents of the installation DVD-ROM.
The Red Hat Enterprise Linux installation program has the ability to test the integrity of the installation media. It works with the DVD, hard drive ISO, and NFS ISO installation methods. Red Hat recommends that you test all installation media before starting the installation process, and before reporting any installation-related bugs (many of the bugs reported are actually due to improperly-burned DVDs). To use this test, type the following command at the
The public directory used to access the installation files over FTP, NFS, or HTTP is mapped to local storage on the network server. For example, the local directory
/var/www/inst/rhel6 on the network server can be accessed as
In the following examples, the directory on the installation staging server that will contain the installation files will be specified as
. The directory that will be made publicly available via FTP, NFS, or HTTP will be specified as
/publicly/available/directory. For example,
may be a directory you create called
/var/www/html/rhel6, for an HTTP install.
In the following, you will require an ISO image. An ISO image is a file containing an exact copy of the content of a DVD. To create an ISO image from a DVD use the following command:
dvd refers to your DVD drive device.
12.1.1. Preparing for FTP and HTTP installation
Extract the files from the ISO image of the installation DVD and place them in a directory that is shared over FTP or HTTP.
Next, make sure that the directory is shared via FTP or HTTP, and verify client access. Test to see whether the directory is accessible from the server itself, and then from another machine on the same subnet to which you will be installing.
12.1.2. Preparing for an NFS installation
For NFS installation it is not necessary to extract all the files from the ISO image. It is sufficient to make the ISO image itself, the
install.img file, and optionally the
product.img file available on the network server via NFS.
Transfer the ISO image to the NFS exported directory. On a Linux system, run:
Use a SHA256 checksum program to verify that the ISO image that you copied is intact. Many SHA256 checksum programs are available for various operating systems. On a Linux system, run:
is the name of the ISO image file. The SHA256 checksum program displays a string of 64 characters called a hash
. Compare this hash to the hash displayed for this particular image on the Download Software
page on the Red Hat Network (refer to Chapter 1, Obtaining Red Hat Enterprise Linux
). The two hashes should be identical.
images/ directory within the ISO file to a directory named
images/. Enter the following commands:
mount -t iso9660 /path/to/RHEL6.iso /mnt/point -o loop,ro
cp -pr /mnt/point/images /path/images/
Verify that the the
directory contains at least the
file, without which installation cannot proceed. Optionally, the
directory should contain the
file, without which only the packages for a Minimal
installation will be available during the package group selection stage (refer to Section 16.18, “Package Group Selection”
Ensure that the
directory is exported via NFS via an entry in
/etc/exports on the network server.
To export a directory read-only to a specific system, use:
To export a directory read-only to all systems, use:
/publicly/available/directory * (ro)
On the network server, start the NFS daemon (on a Red Hat Enterprise Linux system, use
/sbin/service nfs start). If NFS is already running, reload the configuration file (on a Red Hat Enterprise Linux system use
/sbin/service nfs reload).
Be sure to test the NFS share following the directions in the Red Hat Enterprise Linux Deployment Guide. Refer to your NFS documentation for details on starting and stopping the NFS server.
The Red Hat Enterprise Linux installation program has the ability to test the integrity of the installation media. It works with the DVD, hard drive ISO, and NFS ISO installation methods. We recommend that you test all installation media before starting the installation process, and before reporting any installation-related bugs (many of the bugs reported are actually due to improperly-burned DVDs). To use this test, type the following command at the