cli: improvements to the layout commands when multiple layouts are live

src/garage/admin/mod.rs

@@ -274,8 +274,7 @@ impl AdminRpcHandler {
 	fn gather_cluster_stats(&self) -> String {
 		let mut ret = String::new();
 
-		// Gather storage node and free space statistics
-		// TODO: not only layout.current() ???
+		// Gather storage node and free space statistics for current nodes
 		let layout = &self.garage.system.cluster_layout();
 		let mut node_partition_count = HashMap::<Uuid, u64>::new();
 		for short_id in layout.current().ring_assignment_data.iter() {

src/garage/cli/cmd.rs

@@ -179,7 +179,7 @@ pub async fn cmd_status(rpc_cli: &Endpoint<SystemRpc, ()>, rpc_host: NodeID) ->
 			println!("Your cluster is expecting to drain data from nodes that are currently unavailable.");
 			println!("If these nodes are definitely dead, please review the layout history with");
 			println!(
-				"`garage layout history` and use `garage layout assume-sync` to force progress."
+				"`garage layout history` and use `garage layout skip-dead-nodes` to force progress."
 			);
 		}
 	}
@@ -274,6 +274,6 @@ pub async fn fetch_status(
 		.await??
 	{
 		SystemRpc::ReturnKnownNodes(nodes) => Ok(nodes),
-		resp => Err(Error::Message(format!("Invalid RPC response: {:?}", resp))),
+		resp => Err(Error::unexpected_rpc_message(resp)),
 	}
 }

src/garage/cli/layout.rs

@@ -354,10 +354,14 @@ pub async fn cmd_layout_history(
 		));
 	}
 	format_table(table);
-
 	println!();
+
+	if layout.versions.len() > 1 {
 		println!("==== UPDATE TRACKERS ====");
-	println!("This is the internal data that Garage stores to know which nodes have what data.");
+		println!("Several layout versions are currently live in the version, and data is being migrated.");
+		println!(
+			"This is the internal data that Garage stores to know which nodes have what data."
+		);
 		println!();
 		let mut table = vec!["Node\tAck\tSync\tSync_ack".to_string()];
 		let all_nodes = layout.get_all_nodes();
@@ -373,16 +377,21 @@ pub async fn cmd_layout_history(
 		table[1..].sort();
 		format_table(table);
 
-	if layout.versions.len() > 1 {
 		println!();
 		println!(
-			"If some nodes are not catching up to the latest layout version in the update tracker,"
+			"If some nodes are not catching up to the latest layout version in the update trackers,"
 		);
 		println!("it might be because they are offline or unable to complete a sync successfully.");
 		println!(
-			"You may force progress using `garage layout assume-sync --version {}`",
+			"You may force progress using `garage layout skip-dead-nodes --version {}`",
 			layout.current().version
 		);
+	} else {
+		println!("Your cluster is currently in a stable state with a single live layout version.");
+		println!("No metadata migration is in progress. Note that the migration of data blocks is not tracked,");
+		println!(
+			"so you might want to keep old nodes online until their data directories become empty."
+		);
 	}
 
 	Ok(())
@@ -415,6 +424,7 @@ pub async fn cmd_layout_skip_dead_nodes(
 	}
 
 	let all_nodes = layout.get_all_nodes();
+	let mut did_something = false;
 	for node in all_nodes.iter() {
 		if status.iter().any(|x| x.id == *node && x.is_up) {
 			continue;
@@ -422,19 +432,28 @@ pub async fn cmd_layout_skip_dead_nodes(
 
 		if layout.update_trackers.ack_map.set_max(*node, opt.version) {
 			println!("Increased the ACK tracker for node {:?}", node);
+			did_something = true;
 		}
 
 		if opt.allow_missing_data {
 			if layout.update_trackers.sync_map.set_max(*node, opt.version) {
 				println!("Increased the SYNC tracker for node {:?}", node);
+				did_something = true;
 			}
 		}
 	}
 
+	if did_something {
 		send_layout(rpc_cli, rpc_host, layout).await?;
 		println!("Success.");
-
 		Ok(())
+	} else if !opt.allow_missing_data {
+		Err(Error::Message("Nothing was done, try passing the `--allow-missing-data` flag to force progress even when not enough nodes can complete a metadata sync.".into()))
+	} else {
+		Err(Error::Message(
+			"Sorry, there is nothing I can do for you. Please wait patiently. If you ask for help, please send the output of the `garage layout history` command.".into(),
+		))
+	}
 }
 
 // --- utility ---
@@ -448,7 +467,7 @@ pub async fn fetch_layout(
 		.await??
 	{
 		SystemRpc::AdvertiseClusterLayout(t) => Ok(t),
-		resp => Err(Error::Message(format!("Invalid RPC response: {:?}", resp))),
+		resp => Err(Error::unexpected_rpc_message(resp)),
 	}
 }
 

src/garage/cli/util.rs

@@ -450,6 +450,8 @@ pub fn print_block_info(
 
 	if refcount != nondeleted_count {
 		println!();
-		println!("Warning: refcount does not match number of non-deleted versions");
+		println!(
+			"Warning: refcount does not match number of non-deleted versions (see issue #644)."
+		);
 	}
 }