Storage Devices

You can install Red Hat Enterprise Linux on a large variety of storage devices. You can see basic, locally accessible, storage devices in the Installation Destination page, as described in Section 6.10,

“Installation Destination”. To add a specialized storage device, click the Add a disk button in the Specialized & Network Disks section of the screen.

Figure 6.32. Storage Space Overview

Note

Monitoring of LVM and software RAID devices by the m deventd daemon is not performed during installation.

6.11.1. The Storage Devices Selection Screen

The storage device selection screen displays all storage devices to which the Anaconda installation program has access.

The devices are grouped under the following tabs:

Multipath Devices

Storage devices accessible through more than one path, such as through multiple SCSI controllers or Fiber Channel ports on the same system.

The installation program only detects multipath storage devices with serial numbers that are 16 or 32 characters long.

Other SAN Devices

Devices available on a Storage Area Network (SAN).

Firmware RAID

Storage devices attached to a firmware RAID controller.

Figure 6.33. Tabbed Overview of Specialized Storage Devices

To configure an iSCSI device, click the Add iSCSI T arget button. To configure a FCoE (Fibre Channel over Ethernet) device, click the Add FCoE SAN button. Both buttons are located in the lower right corner of the screen.

The overview page also contains the Search tab that allows you to filter storage devices either by their World Wide Identifier (WWID) or by the port, target, or logical unit number (LUN) at which they are

accessed.

Figure 6.34 . The Storage Devices Search Tab

The Search tab contains the Search By drop-down menu to select searching by port, target, LUN, or WWID. Searching by WWID or LUN requires additional values in the corresponding input text fields. Click the Find button to start the search.

Each device is presented on a separate row, with a check box to its left. Click the check box to make the device available during the installation process. Later in the installation process, you can choose to install Red Hat Enterprise Linux onto any of the devices selected here, and can choose to automatically mount any of the other devices selected here as part of the installed system.

Note that the devices that you select here are not automatically erased by the installation process.

Selecting a device on this screen does not, in itself, place data stored on the device at risk. Also note that any devices that you do not select here to form part of the installed system can be added to the system after installation by modifying the /etc/fstab file.

Important

Any storage devices that you do not select on this screen are hidden from Anaconda entirely. To chain load the Red Hat Enterprise Linux boot loader from a different boot loader, select all the devices presented in this screen.

When you have selected the storage devices to make available during installation, click Done to return to the Installation Destination screen.

6.11.1.1. Advanced Storage Options

To use an advanced storage device, you can configure an iSCSI (SCSI over TCP/IP) target or FCoE (Fibre Channel over Ethernet) SAN (Storage Area Network) by clicking the appropriate button in the lower right corner of the Installation Destination screen. See Appendix B, iSCSI Disks for an introduction to iSCSI.

Figure 6.35. Advanced Storage Options

6.11.1.1.1. Configuring iSCSI Parameters

When you have clicked the Add iSCSI target... button, the Add iSCSI Storage T arget dialog appears.

Figure 6.36. The iSCSI Discovery Details Dialog

To use iSCSI storage devices for the installation, Anaconda must be able to discover them as iSCSI targets and be able to create an iSCSI session to access them. Each of these steps might require a user name and password for CHAP (Challenge Handshake Authentication Protocol) authentication. Additionally, you can configure an iSCSI target to authenticate the iSCSI initiator on the system to which the target is attached (reverse CHAP), both for discovery and for the session. Used together, CHAP and reverse CHAP are called mutual CHAP or two-way CHAP. Mutual CHAP provides the greatest level of security for iSCSI connections, particularly if the user name and password are different for CHAP authentication and reverse CHAP authentication.

Note

Repeat the iSCSI discovery and iSCSI login steps as many times as necessary to add all required iSCSI storage. However, you cannot change the name of the iSCSI initiator after you attempt discovery for the first time. To change the iSCSI initiator name, you must restart the installation.

Use the Add iSCSI Storage T arget dialog to provide Anaconda with the information necessary to discover the iSCSI target.

1. Enter the IP address of the iSCSI target in the T arget IP Address field.

2. Provide a name in the iSCSI Initiator Nam e field for the iSCSI initiator in iSCSI qualified name (IQN) format. A valid IQN entry contains:

the string iqn. (note the period)

a date code that specifies the year and month in which your organization's Internet domain or subdomain name was registered, represented as four digits for the year, a dash, and two digits for the month, followed by a period. For example, represent September 2010 as 2010-09.

your organization's Internet domain or subdomain name, presented in reverse order with the top-level domain first. For example, represent the subdomain storage.exam ple.com as

com .exam ple.storage

a colon followed by a string that uniquely identifies this particular iSCSI initiator within your domain or subdomain. For example, :diskarrays-sn-a8675309

A complete IQN can therefore look as follows:

iqn.2010-09.storage.exam ple.com :diskarrays-sn-a8675309 . Anaconda pre-populates the iSCSI Initiator Nam e field with a name in this format to help you with the structure.

For more information on IQNs , see 3.2.6. iSCSI Names in RFC 3720 – Internet Small Computer Systems Interface (iSCSI) available from http://tools.ietf.org/html/rfc3720#section-3.2.6 and 1. iSCSI Names and Addresses in RFC 3721 – Internet Small Computer Systems Interface (iSCSI) Naming and Discovery available from http://tools.ietf.org/html/rfc3721#section-1.

3. Use the Discovery Authentication T ype drop-down menu to specify the type of authentication to use for iSCSI discovery. The following options are available:

no credentials CHAP pair

CHAP pair and a reverse pair

4. A. If you selected CHAP pair as the authentication type, provide the user name and password for