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Exam objective 2.204.3 has a weight of 2, and verifies that candidates are able to configure kernel options to support various drives. This includes the LVM to manage hard disk drives and partitions, and software tools to view and modify hard disk settings. You have some tools available to you to tune the kernel and devices. The syscontrol command can be used to modify a number of kernel parameters at run time. The A option lists all of them and their current settings. You can use the same command to modify any of these values. You will find all these values listed in the Proc directory named SIS. The command HDParm can be used to optimize the operation of a disk drive. If you just give it the name of the drive and the device node, the current settings are displayed. To make adjustments to these values, you'll need to experiment. The increase in access speed can be dramatically improved, but be careful, because it's possible to use this utility to make the disk inaccessible. You can use the tune2fs command to adjust file system parameters. You can look at the super block, add a journal to a file system that doesn't have one, and set conditions under which the file system is to be checked. LVM stands for Logical Volume Management. It's a method of managing a group of physical disk drives and partitions as mass storage in a flexible way. When you read the documentation on using LVM you will encounter the term PV which stands for Physical Volume. It's the physical volumes that are combined and made into larger logical partitions. It can even work on shared storage clusters where disks are shared among multiple host computers. It is implemented by the construction of a device map defining which partitions are to compose a logical volume. Now this is implemented for the Linux kernel 2.6 and later. LVM2 is a utility program, a logical volume manager for the Linux kernel. EVMS is the Enterprise Volume Management System which is integrated volume management software. DMCrypt is a transparent disk encryption subsystem. This is part of the device mapper infrastructure. You need to examine these tools. The basic tools are not that difficult to understand, but you need to read through the list of the things that they can adjust so you get a better idea of what they do, and you need to research Logical Volume Management. It is a lot newer than the others and not quite as common, but it will probably be more prominent in the future.