adv-partitioning-logical-grp-vol.rst

Volume Groups and Logical Volumes

Volume groups and logical volumes allows more creative and flexible partitioning schemas to be created than conventional partitioning schemas we have already discussed.

A volume group allows you to gather disks, physical and logical partitions into a single logical pool of storage. This pool of storage can then be partitioned (like a disk) by using a logical volume.

Only disks that have the type lvm, and physical partitions or logical partitions that have filesystem types lvm2 can be grouped together in a volume group.

Note

Once a physical or logical partition is grouped together into a volume group, they cannot be declared in another volume group.

In this example, an extended physical partition that has two logical partitions that have lvm filesystems; and a disk of type lvm are pooled together via a volume group grp1. A logical volume is used to partition further this volume group.

---
partitioning:
  disks:
  - name: sda
    type: msdos
    size: 20480
    partitions:
    - number: 1
      fstype: ext3
      mountPoint: "/boot"
      size: 1024
    - number: 2
      fstype: linux-swap
      size: 1024
    - number: 3
      fstype: extended
      size: 18432
      partitions:
      - number: 5
        fstype: lvm2
        size: 9216
      - number: 6
        fstype: lvm2
        size: 9216
  - name: sdb
    type: lvm
    size: 122880
  volumeGroups:
  - name: grp1
    physicalVolumes:
    - name: sda5
    - name: sda6
    - name: sdb
  logicalVolumes:
  - name: vol1
    vg_name: grp1
    fstype: ext3
    mountPoint: "/home"
    size: 4098
  - name: vol2
    vg_name: grp1
    fstype: ext3
    mountPoint: "/space"
    size: 64
    grow: true

If you are using JSON:

{
    "partitioning": {
        "disks": [
          {
            "name": "sda",
            "type": "msdos",
            "size": 20480,
            "partitions": [
              {
                "number": 1,
                "fstype": "ext3",
                "mountPoint": "/boot",
                "size": 1024
              },
              {
                "number": 2,
                "fstype": "linux-swap",
                "size": 1024
              },
              {
                "number": 3,
                "fstype": "extended",
                "size": 18432,
                "partitions": [
                  {
                    "number": 5,
                    "fstype": "lvm2",
                    "size": 9216
                  },
                  {
                    "number": 6,
                    "fstype": "lvm2",
                    "size": 9216
                  }
                ]
              }
            ]
          },
          {
            "name": "sdb",
            "type": "lvm",
            "size": 122880
          }
        ],
        "volumeGroups": [
          {
            "name": "grp1",
            "physicalVolumes": [
              {
                "name": "sda5"
              },
              {
                "name": "sda6"
              },
              {
                "name": "sdb"
              }
            ]
          }
        ],
        "logicalVolumes": [
          {
            "name": "vol1",
            "vg_name": "grp1",
            "fstype": "ext3",
            "mountPoint": "/home",
            "size": 4098
          },
          {
            "name": "vol2",
            "vg_name": "grp1",
            "fstype": "ext3",
            "mountPoint": "/space",
            "size": 64,
            "grow": true
          }
        ]
    }
}