[pve-devel] [PATCH v2 pve-docs] vzdump: add section describing PBS change detection mode

[Christian Ebner]

Add a concise section about what PBS change detection mode is and
what it affects, including a table with a description of the modes.

Signed-off-by: Christian Ebner <c.ebner at proxmox.com>
---
 vzdump.adoc | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/vzdump.adoc b/vzdump.adoc
index 9b1cb61..4607e40 100644
--- a/vzdump.adoc
+++ b/vzdump.adoc
@@ -175,6 +175,30 @@ fleecing image up-front. On a thinly provisioned storage, the fleecing image can
 grow to the same size as the original image only if the guest re-writes a whole
 disk while the backup is busy with another disk.
 
+CT Change Detection Mode
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+Setting the change detection mode defines the encoding format for the pxar
+archives and how changed and unchanged files are handled for container backups
+with Proxmox Backup Server as target.
+
+Backups of VMs or to other storage backends are not affected by this setting.
+
+There are 3 change detection modes available:
+
+[width="100%",cols="<m,4d",options="header"]
+|===============================================================================
+| Mode     | Description
+| Default  | Read and encode all files into a single archive, using the pxar
+format version 1.
+| Data     | (EXPERIMENTAL): Read and encode all files, but split data and
+metadata into separate streams, using the pxar format version 2.
+| Metadata | (EXPERIMENTAL): Split streams and use archive format version 2 like
+`Data`, but use metadata archive of previous snapshot (if one exists) to detect
+unchanged files, and reuse their data chunks without reading file contents from
+disk, whenever possible.
+|===============================================================================
+
 Backup File Names
 -----------------
 
-- 
2.39.2