j3d1/webvirtcloud
1
0
Fork 0
mirror of https://github.com/retspen/webvirtcloud synced 2026-11-09 03:36:48 +00:00
Code Issues Projects Releases Wiki Activity

feat(instances): external snapshots can freeze the guest file systems

Browse source 
A disk-only snapshot of a running VM is crash-consistent: data the
guest has not written yet is missing from it. With a connected QEMU
guest agent, the snapshot form now offers to freeze the guest's file
systems while the disks are snapshotted (libvirt's QUIESCE flag); the
box is checked by default and can be cleared. It is offered only for a
running VM whose agent is connected, and not together with memory:
libvirt accepts quiesce only for disk-only snapshots, and a memory
snapshot keeps the whole guest state anyway. A request that does not
fit is refused before libvirt is called.
This commit is contained in:
catborise 2026-10-13 10:33:17 +03:00
parent 64ea12b0ce
commit f766890825
7 changed files with 68 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

16
vrtManager/instance.py
View file

@ -34,6 +34,7 @@ try:
VIR_MIGRATE_UNSAFE,
VIR_DOMAIN_SNAPSHOT_CREATE_ATOMIC,
VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY,
VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE,
VIR_DOMAIN_SNAPSHOT_REVERT_PAUSED,
VIR_DOMAIN_SNAPSHOT_REVERT_RUNNING,
VIR_ERR_CONFIG_UNSUPPORTED,
@ -1575,14 +1576,23 @@ class wvmInstance(wvmConnect):
</domainsnapshot>"""
self._snapshotCreateXML(xml, 0)
def create_external_snapshot(self, name, desc="", memory=False):
def create_external_snapshot(self, name, desc="", memory=False, quiesce=False):
"""A disk-only snapshot, or with memory too (running VMs only). Every
disk gets a libvirt-named overlay next to it; the memory file goes
next to the first disk."""
next to the first disk. quiesce: the guest agent freezes the guest's
file systems for a disk-only snapshot of a running VM (libvirt
accepts it only without memory, which keeps the whole state anyway)."""
if not SNAPSHOT_NAME.fullmatch(name):
raise util.OperationError(
"Snapshot names are 1-64 letters, digits, '.', '_' or '-' and do not start with '.'"
)
if quiesce:
if memory:
raise util.OperationError("A snapshot with memory is not quiesced; it keeps the whole guest state")
if self.get_status() != 1:
raise util.OperationError("Only a running VM's file systems can be frozen")
if not self.is_agent_ready():
raise util.OperationError("The QEMU guest agent is not connected; it freezes the file systems")
self._check_snapshot_state()
if self.instance.snapshotListNames(VIR_DOMAIN_SNAPSHOT_LIST_INTERNAL):
raise util.OperationError("The VM has internal snapshots; external snapshots cannot be mixed with them")
@ -1610,6 +1620,8 @@ class wvmInstance(wvmConnect):
flags = VIR_DOMAIN_SNAPSHOT_CREATE_ATOMIC
if not memory:
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY
if quiesce:
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE
self._snapshotCreateXML(xml, flags)
self._refresh_pools_after_snapshot()