doc: update Key Idea in cephfs-mirroring.rst

Updates the snapdiff feature and it's url.

Signed-off-by: Jos Collin <jcollin@redhat.com>
(cherry picked from commit 629922bf6a0905cc87707f5e2d027f6320aafd99)

diff --git a/doc/dev/cephfs-mirroring.rst b/doc/dev/cephfs-mirroring.rst
index a804a0075995f88714a9e61a083b076dca709b45..e09fed213f2300b9ceff2bf6ed605e9b603a065f 100644 (file)
--- a/doc/dev/cephfs-mirroring.rst
+++ b/doc/dev/cephfs-mirroring.rst
@@ -17,12 +17,10 @@ Key Idea
 --------
 
 For a given snapshot pair in a directory, `cephfs-mirror` daemon will rely on
-readdir diff to identify changes in a directory tree. The diffs are applied to
+`CephFS Snapdiff Feature` to identify changes in a directory tree. The diffs are applied to
 directory in the remote file system thereby only synchronizing files that have
 changed between two snapshots.
 
-This feature is tracked here: https://tracker.ceph.com/issues/47034.
-
 Currently, snapshot data is synchronized by bulk copying to the remote
 filesystem.
 
@@ -407,3 +405,5 @@ Feature Status
 --------------
 
 `cephfs-mirror` daemon is built by default (follows `WITH_CEPHFS` CMake rule).
+
+.. _CephFS Snapdiff Feature: https://croit.io/blog/cephfs-snapdiff-feature