2 Mass Storage Over Ip Networks-Iscsi; Setting Up An Iscsi Target - Novell LINUX ENTERPRISE SERVER 10 SP2 - INSTALLATION AND ADMINISTRATION Installation Manual

12
Mass Storage over IP
Networks—iSCSI
One of the central tasks in computer centers and when operating servers is providing
hard disk capacity for server systems. Fiber channel is often used for this purpose in
the mainframe sector. So far, UNIX computers and the majority of servers are not
connected to central storage solutions.
linux-iSCSI provides an easy and reasonably inexpensive solution for connecting Linux
computers to central storage systems. In principle, iSCSI represents a transfer of SCSI
commands on the IP level. If a program starts an inquiry for such a device, the operating
system produces the necessary SCSI commands. These are then embedded in IP packages
and encrypted as necessary by software that is commonly known as an iSCSI initiator.
The packages are then transferred to the corresponding iSCSI remote station, also called
iSCSI target.
Many storage solutions provide access over iSCSI, but it is also possible to run a Linux
server that provides an iSCSI target. In this case, it is important to set up the Linux
server optimized for file system services. The iSCSI target just accesses block devices
in Linux. Therefore it is possible to use RAID solutions to increase disk space as well
as a lot of memory to improve data caching. For more information about RAID, also
see Section 7.2, "Soft RAID Configuration" (page 123).

12.1 Setting Up an iSCSI Target

SUSE® Linux Enterprise Server comes with an open source iSCSI target solution that
evolved from the Ardis iSCSI target. A basic setup can be done with YaST, but to take
full advantage of iSCSI, a manual setup is required.
Mass Storage over IP Networks—iSCSI 271