- #Logical volume manager windows update
- #Logical volume manager windows driver
- #Logical volume manager windows code
- #Logical volume manager windows windows
The corresponding driver for LVM is called VxConfig. When any configuration changes are made, DMConfig reflects the change in a memory copy of the database.
#Logical volume manager windows update
DMConfig is a driver that can read and update the LDM database. In reality, LDM and LVM are implemented as four different drivers:ġ.
#Logical volume manager windows code
The idea is to reduce code size and complexity for normal runtime situations. LDM and LVM are referred to as if they were a single entity, but each one is implemented as four different drivers, each with a varying amount of functionality.
#Logical volume manager windows windows
Table 6.1 summarizes the capabilities of the three major volume managers available for Windows 2000 and Windows Server 2003 products. Performance by storing data in a way that it can be retrieved efficiently. The volume manager also can concatenate multiple partitions from multiple disks into a single larger volume.ĭata protection by storing data redundantly (using some form of RAID RAID is described in Chapter 9) or storing the data with a checksum. Storage virtualization wherein a file system does not need to know which physical disk the file system is residing on. The VERITAS Logical Volume Manager ( LVM ) that is available from VERITAS as a commercial product and functionally is a superset of the Logical Disk Manager.Īll of the volume managers listed here provide functionality that can be summarized as follows : The Logical Disk Manager ( LDM ) that ships natively with Windows 2000 and Windows Server 2003. In Windows 2000, FtDisk is always loaded because it handles all volumes on basic disks. In Windows NT 4.0, the FtDisk driver was only optionally loaded because it dealt only with enhanced volume functionality such as fault tolerance. The FtDisk Manager that ships natively with Windows 2000 and Windows Server 2003. This section concentrates on describing the functionality of volumes in the post-Windows 2000 world and relates that functionality to the three specific volume managers that are available for the Windows operating system in the post-Windows 2000 world: Volume managers and how they fit into the Windows storage stack were discussed in Chapter 1.
Volumes are implemented in the Windows Server family by a device driver generically referred to as a volume manager. The disk partitions themselves may be soft partitions (existing on dynamic disks) or hard partitions (built on top of basic disks). In that case, using the additional Abstraction layer of LVM may be unnecessary.As explained earlier in this chapter, volumes are an abstraction built on top of disk partitions. If you use the Btrfs file system, its Subvolume feature will also give you the benefit of having a flexible layout. There is no official support in most other OS (FreeBSD, Windows.).Īdditional steps in setting up the system, more complicated. Snapshots allow you to backup a frozen copy of the file system, while keeping service downtime to a minimum. Online/live migration of LV being used by services to different disks without having to restart services. File systems on them still need to be resized, but some support online resizing. Resize/create/delete logical and physical volumes online. It does not depend on the position of the LV within VG, there is no need to ensure surrounding available space. Resize logical volumes regardless of their order on disk.
Have logical volumes stretched over several disks.Ĭreate small logical volumes and resize them "dynamically" as they get more filled. LVM gives you more flexibility than just using normal hard drive partitions: Then, when the partitions start to fill up, they can be expanded as necessary. You can also allocate minimal amounts of space for each logical volume and leave some of the disk unallocated. One of the big advantages of LVM is that you can most easily reduce the size of one partition, and use it on other partitions for example, without data loss. You should read some more specified info here at The Linux Logical Volume ManagerĪlso there's some good information at A Beginner's Guide To LVM With LVM, "logical" partitions can span across physical hard drives and can be resized (unlike traditional ext3 "raw" partitions).Ī physical disk is divided into one or more physical volumes (Pvs), and logical volume groups (VGs) are created by combining PVs. Logical volume management is a widely-used technique for deploying logical rather than physical storage.