Re: [libvirt PATCH 1/3] include: Introduce VIR_MIGRATE_ASSUME_SHARED_STORAGE
On Tue, Oct 31, 2023 at 18:12:58 +0100, Andrea Bolognani wrote:
Signed-off-by: Andrea Bolognani <abologna(a)redhat.com>
---
include/libvirt/libvirt-domain.h | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index a1902546bb..37c55c5ae8 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -1100,6 +1100,20 @@ typedef enum {
* Since: 8.5.0
*/
VIR_MIGRATE_ZEROCOPY = (1 << 20),
+
+ /* Assume that the storage used for VM disks is shared even when
+ * it appears to be local storage.
I'll try to come up with a safety label to put here as this has the
potential to be a very shiny tempting foot-gun for anyone getting the
warning about migration being unsafe.
+ *
+ * This can be the case, for example, when a directory is mounted
+ * using NFS on the destination host but is bind-mounted on the
+ * source host, because the latter happens to be the host that
+ * storage is physically attached to.
Technically it doesn't even need to be bind mounted, you can simply use
directly what NFS is exporting. I presume bind-mount is what CNV does in
this case, but please document the common one.
+ *
+ * Effectively a subset of VIR_MIGRATE_UNSAFE.
+ *
+ * Since: 9.10.0
+ */
+ VIR_MIGRATE_ASSUME_SHARED_STORAGE = (1 << 21),
} virDomainMigrateFlags;
--
2.41.0