diff --git a/references/virtual-disk-cache-modes.xml b/references/virtual-disk-cache-modes.xml index 1c70c1f62..ef4e250e4 100644 --- a/references/virtual-disk-cache-modes.xml +++ b/references/virtual-disk-cache-modes.xml @@ -87,12 +87,7 @@ guests are ignored. Using this mode implies that the user prioritizes performance gain over data security. - - - Using the unsafe mode can cause data loss in case of a host - failure. Do not use this mode for production workloads. - - + @@ -123,7 +118,7 @@ This mode informs the guest of the presence of a write cache, and it relies on the guest to send flush commands as needed to maintain data integrity within its disk - image. + image. @@ -139,8 +134,9 @@ This mode is similar to writeback caching, except the guest flush - commands are ignored. This means a higher risk of data loss due to host failure. + commands are ignored. + @@ -159,16 +155,23 @@ factors. If the guest storage is hosted on a clustered file system, is read-only, or is marked shareable, then the cache mode is ignored when determining if migration can be allowed. Otherwise, &libvirt; does not allow migration unless the cache mode is set to - none. However, this restriction can be overridden with the - option to the migration APIs, which is also supported by - virsh. For example: + none. + + + If you need to do a live migration with a different cache mode than + none, use the option, for example: + &prompt.user;virsh migrate --live --unsafe + + Be aware that this option may cause loss of data that the migrated VM is caching. + + - The cache mode none is required for the AIO mode setting - native. If another cache mode is used, the AIO mode is silently switched - back to the default threads. + When using the native asynchronous I/O mode (AIO) in &libvirt;, the + cache mode none is required. Using a different caching mode switches the + AIO mode back to the default threads. diff --git a/tasks/virtual-disk-cache-mode-configure-using-virsh.xml b/tasks/virtual-disk-cache-mode-configure-using-virsh.xml index 9f45f8e8b..781534893 100644 --- a/tasks/virtual-disk-cache-mode-configure-using-virsh.xml +++ b/tasks/virtual-disk-cache-mode-configure-using-virsh.xml @@ -41,7 +41,7 @@ Id Name State &prompt.sudo;virsh domblklist sle15sp5 Target Source ------------------------------------------ -vda /home/tbazant/virt/sle15.qcow2 +vda /home/example-user/virt/sle15.qcow2 sda - @@ -57,7 +57,7 @@ sda - <disk type='file' device='disk'> <driver name='qemu' type='qcow2' cache='writethrough'/> - <source file='/home/tbazant/virt/sle15.qcow2'/> + <source file='/home/example-user/virt/sle15.qcow2'/> <target dev='vda' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/> </disk> @@ -77,11 +77,6 @@ sda - &prompt.sudo;sudo virsh define virt/sle15sp5.xml Domain 'sle15sp5' defined from virt/sle15sp5.xml - - - You may have to restart a running VM for the changes to take effect. - - diff --git a/tasks/virtual-disk-cache-mode-configure-using-vmm.xml b/tasks/virtual-disk-cache-mode-configure-using-vmm.xml index 49b9e4e10..f69df99d9 100644 --- a/tasks/virtual-disk-cache-mode-configure-using-vmm.xml +++ b/tasks/virtual-disk-cache-mode-configure-using-vmm.xml @@ -54,11 +54,6 @@ Confirm with Apply. - - - You may have to restart a running VM for the changes to take effect. - -