Merge pull request #5179 from xiang90/doc_di

doc: link to recovery.md

Documentation/docs.md

@@ -23,7 +23,7 @@ Want to operate etcd clusters? Start by setting up a cluster on multiple machine
  - Security
  - Monitoring
  - [Maintenance][maintenance]
- - Disaster recovery
+ - [Disaster recovery][recovery]
  - Performance
 
 ## Learning
@@ -44,4 +44,5 @@ Want to learn more about the concepts and internals behind etcd? Read the follow
 [glossary]: learning/glossary.md
 [interacting]: dev-guide/interacting_v3.md
 [local_cluster]: dev-guide/local_cluster.md
-[maintenance]: op_guide/maintenance.md
+[maintenance]: op_guide/maintenance.md
+[recovery]: op_guide/recovery.md

Documentation/op_guide/recovery.md

@@ -4,6 +4,8 @@ etcd is designed to withstand machine failures. An etcd cluster automatically re
 
 To recover from disastrous failure, etcd provides snapshot and restore facilities to recreate the cluster without data loss.
 
+TODO(xiangli): add note to clarify this only recovers for the kv store of etcd3.
+
 ### Snapshotting the keyspace
 
 Recovering a cluster first needs a snapshot of the keyspace from an etcd member. A snapshot may either be taken from a live member with the `etcdctl snapshot save` command or by copying the `member/snap/db` file from an etcd data directory. For example, the following command snapshots the keyspace served by `$ENDPOINT` to the file `snapshot.db`:
@@ -57,4 +59,3 @@ $ etcd \
 ```
 
 Now the restored etcd cluster should be available and serving the keyspace given by the snapshot.
-