From: Dylan Whyte <d.whyte@proxmox.com>
To: Stefan Reiter <s.reiter@proxmox.com>, pve-devel@lists.proxmox.com
Subject: Re: [pve-devel] [PATCH docs 1/2] vzdump: add section about live-restore
Date: Thu, 22 Apr 2021 12:30:06 +0200 [thread overview]
Message-ID: <a71f1d28-194c-c858-53eb-1171880b83f0@proxmox.com> (raw)
In-Reply-To: <20210422082507.22747-1-s.reiter@proxmox.com>
Hi,
I just made some very minor suggestions inline, but overall it's good (i
had to search extra-hard for issues) :)
Reviewed-by: Dylan Whyte <d.whyte@proxmox.com>
On 4/22/21 10:25 AM, Stefan Reiter wrote:
> Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
> ---
>
> 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
s/property for/argument of/
s/immediately/as soon/
> +begins. Data is copied in the background, chunks that the VM is actively
s/, chunks/, and chunks/
or to reformulate: "Data is copied in the background, prioritizing
chunks that the VM is actively accessing."
> +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
s/once loaded/once loaded,/
> + 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
s/unspecified/undefined/
> + 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
s/are started/have been started/
s/already operational/operational/
> +background task keeps copying seldomly used data.
s/keeps/continues/
> +
> [[vzdump_configuration]]
> Configuration
> -------------
prev parent reply other threads:[~2021-04-22 10:30 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-22 8:25 Stefan Reiter
2021-04-22 8:25 ` [pve-devel] [PATCH docs 2/2] vzdump: add section about single file restore Stefan Reiter
2021-04-22 10:31 ` Dylan Whyte
2021-04-22 10:30 ` Dylan Whyte [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=a71f1d28-194c-c858-53eb-1171880b83f0@proxmox.com \
--to=d.whyte@proxmox.com \
--cc=pve-devel@lists.proxmox.com \
--cc=s.reiter@proxmox.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox