iSCSI

FlexBoot enables an iSCSI-boot of an OS located on a remote iSCSI target. It has a built-in iSCSI initiator which can connect to the remote iSCSI target and load from it the kernel and initrd. There are two instances of connection to the remote iSCSI target: the first is for get- ting the kernel and initrd via FlexBoot, and the second is for loading other parts of the OS via initrd.

If you choose to continue loading the OS (after boot) through the HCA device driver, please verify that the initrd image includes the HCA driver.

It is recommended to install to an iSCSI target using the same port performing the following:

1. Connect to the iSCSI target to retrieve various information from it.
   Due to the step above, FlexBoot will register the remote target by hooking BIOS interrupt 13.

2. Download the installation image using the same port by supplying the file name in the client's DHCP configuration file along with the root path.

Prerequisites

• Make sure that an iSCSI Target is installed on your server side.
  You can download and install an iSCSI Target from the following location: http://sourceforge.net/projects/iscsitarget/files/iscsitarget/

• Dedicate a partition on your iSCSI Target on which you will later install the operating system

• Configure your iSCSI Target to work with the partition you dedicated. If, for example, you choose partition /dev/sda5, then edit the iSCSI Target configuration file /etc/ietd.conf to include the following line under the iSCSI Target iqn line:

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  Lun 0 Path=/dev/sda5,Type=fileio 
          

  Example of an iSCSI Target iqn line:

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  Target iqn.2007-08.7.3.4.10:iscsiboot 
          

• Start your iSCSI Target.
  Example:

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  host1# /etc/init.d/iscsitarget start
          

Configuring the DHCP Server to Boot From an iSCSI Target

1. Configure DHCP as described in section " Preparing the DHCP Server in Linux "

2. Edit your DHCP configuration file (/etc/dhcpd.conf) and add the following lines for the machine(s) you wish to boot from the iSCSI target:

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   Filename "";
   option root-path "iscsi:iscsi_target_ip::::iscsi_target_iqn";
           

The following is an example for configuring an IB/ETH device to boot from an iSCSI target:

            

            
host host1{ filename "";
option root-path "iscsi:iscsi_target_ip::::iscsi_target_iqn";
 
For a ConnectX device with ports configured as InfiniBand, comment out# the follow- ing line
option dhcp-client-identifier = ff:00:00:00:00:00:02:00:00:02:c9:00:00:02:c9:03:00:00:10:39;
For a ConnectX device with ports configured as Ethernet, comment out# the following line
hardware ethernet 00:02:c9:00:00:bb;
}