snapshot
The snapshot
role enables users to add/remove snapshots
on target machines. This role can be used to configure snapshots
via:
- LVM
Requirements
None
Role Variables
snapshot_lvm_action
This variable is required. It supports one of the following values:
snapshot
: Take snapshots of the specified VGs/LVscheck
: Validate that snapshot names don't have conflicts and there is sufficient space to take the snapshotsremove
: Remove snapshots that conform to the specified prefix and patternrevert
: Revert to snapshots that are specified by either the pattern or set. If either the source LV or snapshot are open, the merge is deferred until the next time the server reboots and the source logical volume is activated.extend
: Extend snapshot to have at least snapshot_lvm_percent_space_required space allocated to the snapshot. Allocations are rounded up to the next multiple of the volume group extent size.mount
: Mount a filesystem on a mount pointumount
: Unmount a filesytem
snapshot_lvm_set
The snapshot role supports sets of volumes. Sets may contain any number of volumes. Sets are defined in the following format:
snapshot_lvm_set:
name: snapset1
volumes:
- name: snapshot VG1 LV1
vg: test_vg1
lv: lv1
percent_space_required: 15
mountpoint: /mnt/lv1_mp
- name: snapshot VG2 LV3
vg: test_vg2
lv: lv3
mountpoint: /mnt/lv3_mp
percent_space_required: 15
- name: snapshot VG2 LV4
vg: test_vg2
lv: lv4
mountpoint: /mnt/lv4_mp
percent_space_required: 15
- name: snapshot VG3 LV7
vg: test_vg3
lv: lv7
mountpoint: /mnt/lv7_mp
percent_space_required: 15
If the user is indicating the mount action and wants the origin of the snapshot to be mounted rather than the snapshot, the set would be defined with the additional field "mount_origin" for any entry that it applies, for example:
snapshot_lvm_set:
name: snapset1
volumes:
- name: snapshot VG1 LV1
vg: test_vg1
lv: lv1
percent_space_required: 15
mountpoint: /mnt/lv1_mp
mount_origin: false
- name: snapshot VG2 LV3
vg: test_vg2
lv: lv3
mountpoint: /mnt/lv3_mp
percent_space_required: 15
mount_origin: true
- name: snapshot VG2 LV4
vg: test_vg2
lv: lv4
mountpoint: /mnt/lv4_mp
percent_space_required: 15
mount_origin: false
- name: snapshot VG3 LV7
vg: test_vg3
lv: lv7
mountpoint: /mnt/lv7_mp
percent_space_required: 15
mount_origin: true
The mount_origin flag defaults to false, so it is not necessary when the user is mounting the snapshot rather than the origin.
snapshot_lvm_snapset_name
This variable is required. snapshot_lvm_snapset_name is a string that will be appended to the name of the LV when the snapshot set is created. It will be used to identify members of the set. It must be at least one character long and contain valid characters for use in an LVM volume name. A to Z, a to z, 0 to 9, underscore (_), hyphen (-), dot (.), and plus (+) are valid characters. When used inside of a snapset definition, use name parameter.
If before running the role, the following LVs exist:
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
home rhel -wi-ao---- 1.00g
root rhel -wi-ao---- 35.00g
swap rhel -wi-ao---- <3.88g
lv1_vg1 vg1 -wi-a----- 1.00g
lv2_vg1 vg1 -wi-a----- 40.00m
lv1_vg2 vg2 -wi-a----- 1.00g
lv2_vg2 vg2 -wi-a----- 80.00m
lv1_vg3 vg3 -wi-a----- 1.00g
lv3_vg3 vg3 -wi-a----- 120.00m
If snapshot_lvm_snapset_name is set to "_snapset1", running the role will result in the following:
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
home_snapset1 rhel swi-a-s--- 104.00m home 0.00
root_snapset1 rhel swi-a-s--- 3.50g root 0.01
swap_snapset1 rhel swi-a-s--- 400.00m swap 0.00
home rhel owi-aos--- 1.00g
root rhel owi-aos--- 35.00g
swap rhel owi-aos--- <3.88g
lv1_vg1_snapset1 vg1 swi-a-s--- 104.00m lv1_vg1 0.00
lv2_vg1_snapset1 vg1 swi-a-s--- 8.00m lv2_vg1 0.00
lv1_vg1 vg1 owi-a-s--- 1.00g
lv2_vg1 vg1 owi-a-s--- 40.00m
lv1_vg2_snapset1 vg2 swi-a-s--- 104.00m lv1_vg2 0.00
lv2_vg2_snapset1 vg2 swi-a-s--- 12.00m lv2_vg2 0.00
lv1_vg2 vg2 owi-a-s--- 1.00g
lv2_vg2 vg2 owi-a-s--- 80.00m
lv1_vg3_snapset1 vg3 swi-a-s--- 104.00m lv1_vg3 0.00
lv3_vg3_snapset1 vg3 swi-a-s--- 16.00m lv3_vg3 0.00
lv1_vg3 vg3 owi-a-s--- 1.00g
lv3_vg3 vg3 owi-a-s--- 120.00m
snapshot_lvm_percent_space_required
This is required for check and snapshot actions if not using sets.
See the LVM man page for lvcreate with the -s (snapshot) and -L (size) options. The snapshot role will ensure that there is at least snapshot_lvm_percent_space_required space available in the VG. When used inside of a snapset definition, use percent_space_required parameter.
Note: LVM will round up size to full physical extent
snapshot_lvm_all_vgs
This is a boolean value with default false. If true the role will snapshot all VGs on the target system. If false, the snapshot_lvm_vg or snapshot_lvm_set must be set.
snapshot_lvm_vg
If set, the role will create snapshots for all the logical volumes in the volume group. If snapshot_lvm_lv is also set, a snapshot will be created for only that logical volume in the volume group. If neither snapshot_lvm_all_vgs or snapshot_lvm_set are set, snapshot_lvm_vg is required. When used inside of a snapset definition, use vg parameter.
snapshot_lvm_lv
If set, the role will create snapshots for the single logical volume in the volume group specified by snapshot_lvm_vg. The parameter requires snapshot_lvm_vg is set to a valid volume group. When used inside of a snapset definition, use lv parameter.
snapshot_lvm_verify_only
If true, the check and remove commands verify that the system is in the correct state. For the remove command, the target system will be searched for any snapshots that would be removed by the remove command without snapshot_lvm_verify_only.
snapshot_lvm_verify_only is intended to be used to double check that the snapshot or remove command have completed the operation correctly.
snapshot_lvm_mountpoint_create
If the mount point specified doesn't currently exist, create the mount point and any parent directories necessary for the mount point. When used inside of a snapset definition, use mountpoint_create parameter.
snapshot_lvm_mountpoint
The mount target for the block device. When used inside of a snapset definition, use mountpoint parameter.
snapshot_lvm_mount_origin
If set to true, mount the origin of the snapshot rather than the snapshot. When used inside of a snapset definition, use mount_origin parameter.
snapshot_lvm_mount_options
Options to pass to the mount command for the filesystem. The argument is a comma separated list. See the man page for mount for details. Note that XFS by default will not allow multiple filesystems with the same UUID to be mounted at the same time. Using the "nouuid" will bypass the duplicate UUID check and allow a snapshot to be mounted at the same time as the snapshot source.
snapshot_lvm_unmount_all
If set to true, unmount all mountpoint for the resulting blockdevice. Linux allows filesystems to be mounted in multiple locations. Setting this flag will unmount all locations.
snapshot_lvm_vg_include
When using snapshot_lvm_all_vgs
, there may be some
subset of all volume groups that you want to use. Set
snapshot_lvm_vg_include
to a regex pattern that matches the
names of the volume groups you want to use and the rest will be
excluded. For example, snapshot_lvm_vg_include: "^sql_db_"
will only operate on volume groups whose names start with
sql_db_
. This uses the Python re.search
.
Variables Exported by the Role
snapshot_facts
Contains volume and mount point information for a given snapset.
For example:
{
"volumes": {
"vg3": [
{
"lv_uuid": "VY7oRQ-zB1q-DzsP-1y7G-J3gL-ci1e-nQXwAy",
"lv_name": "lv1_vg3",
"lv_full_name": "vg3/lv1_vg3",
"lv_path": "/dev/vg3/lv1_vg3",
"lv_size": "1073741824",
"origin": "",
"origin_size": "1073741824",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "owi-a-s---",
"vg_name": "vg3",
"data_percent": "",
"metadata_percent": ""
},
{
"lv_uuid": "Yhn7RG-k7pM-ylf9-NNt8-xuGI-WwrF-i0Pf6T",
"lv_name": "lv1_vg3_snapset2",
"lv_full_name": "vg3/lv1_vg3_snapset2",
"lv_path": "/dev/vg3/lv1_vg3_snapset2",
"lv_size": "322961408",
"origin": "lv1_vg3",
"origin_size": "1073741824",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "swi-a-s---",
"vg_name": "vg3",
"data_percent": "0.00",
"metadata_percent": ""
},
{
"lv_uuid": "NlwbxX-NhwK-IHTj-sV9k-ldZY-Twvj-2SiCVe",
"lv_name": "lv2_vg3",
"lv_full_name": "vg3/lv2_vg3",
"lv_path": "/dev/vg3/lv2_vg3",
"lv_size": "1073741824",
"origin": "",
"origin_size": "1073741824",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "owi-a-s---",
"vg_name": "vg3",
"data_percent": "",
"metadata_percent": ""
},
{
"lv_uuid": "j0RCzX-OVaA-MGDw-ejHO-Eu35-f4yG-VJL2Kr",
"lv_name": "lv2_vg3_snapset2",
"lv_full_name": "vg3/lv2_vg3_snapset2",
"lv_path": "/dev/vg3/lv2_vg3_snapset2",
"lv_size": "322961408",
"origin": "lv2_vg3",
"origin_size": "1073741824",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "swi-aos---",
"vg_name": "vg3",
"data_percent": "0.66",
"metadata_percent": ""
},
{
"lv_uuid": "8kfTDY-22SL-4tC7-vTsR-1R63-zVzq-55qEL3",
"lv_name": "lv3_vg3",
"lv_full_name": "vg3/lv3_vg3",
"lv_path": "/dev/vg3/lv3_vg3",
"lv_size": "125829120",
"origin": "",
"origin_size": "125829120",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "owi-a-s---",
"vg_name": "vg3",
"data_percent": "",
"metadata_percent": ""
},
{
"lv_uuid": "babChm-IzEN-Pf8q-1dxk-BJ9R-3kZb-u91utS",
"lv_name": "lv3_vg3_snapset2",
"lv_full_name": "vg3/lv3_vg3_snapset2",
"lv_path": "/dev/vg3/lv3_vg3_snapset2",
"lv_size": "41943040",
"origin": "lv3_vg3",
"origin_size": "125829120",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "swi-a-s---",
"vg_name": "vg3",
"data_percent": "0.00",
"metadata_percent": ""
}
],
"vg2": [
{
"lv_uuid": "8uMuRW-1KCV-8FTJ-frhX-X39o-V15B-1uEC98",
"lv_name": "lv1_vg2",
"lv_full_name": "vg2/lv1_vg2",
"lv_path": "/dev/vg2/lv1_vg2",
"lv_size": "1073741824",
"origin": "",
"origin_size": "1073741824",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "owi-a-s---",
"vg_name": "vg2",
"data_percent": "",
"metadata_percent": ""
},
{
"lv_uuid": "GGssIK-SHYI-to1m-MhVL-2BDk-PJ8X-dBnL7G",
"lv_name": "lv1_vg2_snapset2",
"lv_full_name": "vg2/lv1_vg2_snapset2",
"lv_path": "/dev/vg2/lv1_vg2_snapset2",
"lv_size": "322961408",
"origin": "lv1_vg2",
"origin_size": "1073741824",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "swi-aos---",
"vg_name": "vg2",
"data_percent": "20.97",
"metadata_percent": ""
},
{
"lv_uuid": "83A9VM-kVEy-sc60-kF14-gKGb-5Ryj-7yDyEG",
"lv_name": "lv2_vg2",
"lv_full_name": "vg2/lv2_vg2",
"lv_path": "/dev/vg2/lv2_vg2",
"lv_size": "83886080",
"origin": "",
"origin_size": "83886080",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "owi-a-s---",
"vg_name": "vg2",
"data_percent": "",
"metadata_percent": ""
},
{
"lv_uuid": "6tVL8A-U1x1-qqUt-WFVG-POsG-msFs-ZbbPq1",
"lv_name": "lv2_vg2_snapset2",
"lv_full_name": "vg2/lv2_vg2_snapset2",
"lv_path": "/dev/vg2/lv2_vg2_snapset2",
"lv_size": "29360128",
"origin": "lv2_vg2",
"origin_size": "83886080",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "swi-a-s---",
"vg_name": "vg2",
"data_percent": "0.00",
"metadata_percent": ""
}
],
"vg1": [
{
"lv_uuid": "UnN0s0-TauJ-csnN-BgC1-3ocI-p8bE-jz0Hd8",
"lv_name": "lv1_vg1",
"lv_full_name": "vg1/lv1_vg1",
"lv_path": "/dev/vg1/lv1_vg1",
"lv_size": "1073741824",
"origin": "",
"origin_size": "1073741824",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "owi-aos---",
"vg_name": "vg1",
"data_percent": "",
"metadata_percent": ""
},
{
"lv_uuid": "5Np7N9-H15x-Go96-fIwL-E0GR-4fVB-clLDW2",
"lv_name": "lv1_vg1_snapset2",
"lv_full_name": "vg1/lv1_vg1_snapset2",
"lv_path": "/dev/vg1/lv1_vg1_snapset2",
"lv_size": "322961408",
"origin": "lv1_vg1",
"origin_size": "1073741824",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "swi-a-s---",
"vg_name": "vg1",
"data_percent": "20.97",
"metadata_percent": ""
},
{
"lv_uuid": "P0LPUQ-CljS-hOEm-U749-yyr9-USE7-1qDc2N",
"lv_name": "lv2_vg1",
"lv_full_name": "vg1/lv2_vg1",
"lv_path": "/dev/vg1/lv2_vg1",
"lv_size": "41943040",
"origin": "",
"origin_size": "41943040",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "owi-a-s---",
"vg_name": "vg1",
"data_percent": "",
"metadata_percent": ""
},
{
"lv_uuid": "FYIBRe-FDiW-PDUE-3l1y-mLzN-bLEg-qF12cz",
"lv_name": "lv2_vg1_snapset2",
"lv_full_name": "vg1/lv2_vg1_snapset2",
"lv_path": "/dev/vg1/lv2_vg1_snapset2",
"lv_size": "16777216",
"origin": "lv2_vg1",
"origin_size": "41943040",
"pool_lv": "",
"lv_tags": "",
"lv_attr": "swi-a-s---",
"vg_name": "vg1",
"data_percent": "0.00",
"metadata_percent": ""
}
]
},
"mounts": {
"/dev/vg3/lv1_vg3": null,
"/dev/vg3/lv1_vg3_snapset2": [
{
"TARGET": "/mnt/database",
"SOURCE": "/dev/mapper/vg3-lv1_vg3_snapset2",
"FSTYPE": "xfs",
"OPTIONS": "rw,relatime,seclabel,attr2,inode64,logbufs=8,logbsize=32k,noquota"
}
],
"/dev/vg3/lv2_vg3": null,
"/dev/vg3/lv2_vg3_snapset2": null,
"/dev/vg3/lv3_vg3": null,
"/dev/vg3/lv3_vg3_snapset2": null,
"/dev/vg2/lv1_vg2": null,
"/dev/vg2/lv1_vg2_snapset2": [
{
"TARGET": "/mnt/production_mnt",
"SOURCE": "/dev/mapper/vg2-lv1_vg2_snapset2",
"FSTYPE": "xfs",
"OPTIONS": "rw,relatime,seclabel,attr2,inode64,logbufs=8,logbsize=32k,noquota"
}
],
"/dev/vg2/lv2_vg2": null,
"/dev/vg2/lv2_vg2_snapset2": null,
"/dev/vg1/lv1_vg1": null,
"/dev/vg1/lv1_vg1_snapset2": [
{
"TARGET": "/mnt/new_mountpoint",
"SOURCE": "/dev/mapper/vg1-lv1_vg1_snapset2",
"FSTYPE": "xfs",
"OPTIONS": "rw,relatime,seclabel,attr2,inode64,logbufs=8,logbsize=32k,noquota"
},
{
"TARGET": "/mnt/other_mp",
"SOURCE": "/dev/mapper/vg1-lv1_vg1_snapset2",
"FSTYPE": "xfs",
"OPTIONS": "rw,relatime,seclabel,attr2,inode64,logbufs=8,logbsize=32k,noquota"
}
],
"/dev/vg1/lv2_vg1": null,
"/dev/vg1/lv2_vg1_snapset2": null
}
}
rpm-ostree
See README-ostree.md
License
MIT