Signed-off-by: Stefan Reiter <[email protected]> --- As discussed off-list, the vzdump section in general seems a bit misorganized, and is certainly missing some references to PBS. Dylan agreed to take a look at it, thanks again for that!
vzdump.adoc | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/vzdump.adoc b/vzdump.adoc index 9453684..0577a97 100644 --- a/vzdump.adoc +++ b/vzdump.adoc @@ -337,6 +337,34 @@ per configured storage, this can be done with: # pvesm set STORAGEID --bwlimit restore=KIBs ---- +Live-Restore +~~~~~~~~~~~~ + +Restoring a large backup can take a long time, in which a guest is still +unavailable. For VM backups stored on a Proxmox Backup Server, this wait +time can be mitigated using the live-restore option. + +Enabling live-restore via either the checkbox in the GUI or the `--live-restore` +property for `qmrestore` causes the VM to start immediately as the restore +begins. Data is copied in the background, chunks that the VM is actively +accessing are prioritized. + +Note that this comes with two caveats: + +* During live-restore, the VM will operate with limited disk read speeds, as + data has to be loaded from the backup server (once loaded it is immediately + available on the destination storage however, so accessing data twice only + incurs the penalty the first time). Write speeds are largely unaffected. +* If the live-restore fails for any reason, the VM will be left in an + unspecified state - that is, not all data might have been copied from the + backup, and it is _most likely_ not possible to keep any data that was written + during the failed restore operation. + +This mode of operation is especially useful for large VMs, where only a small +amount of data is required for initial operation, e.g. web servers - once the OS +and necessary services are started, the VM is already operational, while the +background task keeps copying seldomly used data. + [[vzdump_configuration]] Configuration ------------- -- 2.20.1 _______________________________________________ pve-devel mailing list [email protected] https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
