Appendix F. iSCSI disks in installation program

The Red Hat Enterprise Linux installer can discover and log in to iSCSI disks in two ways:

  • When the installer starts, it checks if the BIOS or add-on boot ROMs of the system support iSCSI Boot Firmware Table (iBFT), a BIOS extension for systems that can boot from iSCSI. If the BIOS supports iBFT, the installer reads the iSCSI target information for the configured boot disk from the BIOS and logs in to this target, making it available as an installation target.

    Important

    To connect automatically to an iSCSI target, activate a network device for accessing the target. To do so, use ip=ibft boot option. For more information, see Network boot options.

  • You can discover and add iSCSI targets manually in the installer’s graphical user interface. For more information, see Configuring storage devices.

    Important

    You cannot place the /boot partition on iSCSI targets that you have manually added using this method - an iSCSI target containing a /boot partition must be configured for use with iBFT. However, in instances where the installed system is expected to boot from iSCSI with iBFT configuration provided by a method other than firmware iBFT, for example using iPXE, you can remove the /boot partition restriction using the inst.nonibftiscsiboot installer boot option.

While the installer uses iscsiadm to find and log into iSCSI targets, iscsiadm automatically stores any information about these targets in the iscsiadm iSCSI database. The installer then copies this database to the installed system and marks any iSCSI targets that are not used for root partition, so that the system automatically logs in to them when it starts. If the root partition is placed on an iSCSI target, initrd logs into this target and the installer does not include this target in start up scripts to avoid multiple attempts to log into the same target.