Volume Groups and Logical VolumesΒΆ
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 us 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
}
]
}
}