diff --git a/packages/ctl/ctl.js b/packages/ctl/ctl.js
index d9eaf1c8..0658725a 100755
--- a/packages/ctl/ctl.js
+++ b/packages/ctl/ctl.js
@@ -188,7 +188,7 @@ instanceCommands.add(new libCommand.Command({
 	}],
 	handler: async function(args, control) {
 		let instanceId = await libCommand.resolveInstance(control, args.instance);
-		await libLink.messages.setLogSubscriptions.send(control, { all: false, instance_ids: [instanceId] });
+		await control.setLogSubscriptions({ instance_ids: [instanceId] });
 		let response = await libLink.messages.createSave.send(control, {
 			instance_id: instanceId,
 		});
@@ -201,7 +201,7 @@ instanceCommands.add(new libCommand.Command({
 	}],
 	handler: async function(args, control) {
 		let instanceId = await libCommand.resolveInstance(control, args.instance);
-		await libLink.messages.setLogSubscriptions.send(control, { all: false, instance_ids: [instanceId] });
+		await control.setLogSubscriptions({ instance_ids: [instanceId] });
 		let response = await libLink.messages.exportData.send(control, {
 			instance_id: instanceId,
 		});
@@ -218,11 +218,12 @@ instanceCommands.add(new libCommand.Command({
 	}],
 	handler: async function(args, control) {
 		let instanceId = await libCommand.resolveInstance(control, args.instance);
-		await libLink.messages.setLogSubscriptions.send(control, { all: false, instance_ids: [instanceId] });
+		await control.setLogSubscriptions({ instance_ids: [instanceId] });
 		let response = await libLink.messages.startInstance.send(control, {
 			instance_id: instanceId,
 			save: args.save || null,
 		});
+		control.keepOpen = args.keepOpen;
 	},
 }));
 
@@ -236,11 +237,12 @@ instanceCommands.add(new libCommand.Command({
 	}],
 	handler: async function(args, control) {
 		let instanceId = await libCommand.resolveInstance(control, args.instance);
-		await libLink.messages.setLogSubscriptions.send(control, { all: false, instance_ids: [instanceId] });
+		await control.setLogSubscriptions({ instance_ids: [instanceId] });
 		let response = await libLink.messages.loadScenario.send(control, {
 			instance_id: instanceId,
 			scenario: args.scenario || null,
 		});
+		control.keepOpen = args.keepOpen;
 	},
 }));
 
@@ -250,7 +252,7 @@ instanceCommands.add(new libCommand.Command({
 	}],
 	handler: async function(args, control) {
 		let instanceId = await libCommand.resolveInstance(control, args.instance);
-		await libLink.messages.setLogSubscriptions.send(control, { all: false, instance_ids: [instanceId] });
+		await control.setLogSubscriptions({ instance_ids: [instanceId] });
 		let response = await libLink.messages.stopInstance.send(control, {
 			instance_id: instanceId,
 		});
@@ -469,12 +471,75 @@ userCommands.add(new libCommand.Command({
 	},
 }));
 
+const logCommands = new libCommand.CommandTree({ name: "log", description: "Log inspection" });
+logCommands.add(new libCommand.Command({
+	definition: ["follow", "follow cluster log", (yargs) => {
+		yargs.options({
+			"all": { describe: "Follow the whole cluster log", nargs: 0, type: "boolean", default: false },
+			"master": { describe: "Follow log of the master server", nargs: 0, type: "boolean", default: false },
+			"slave": { describe: "Follow log of given slave", nargs: 1, type: "string", default: null },
+			"instance": { describe: "Follow log of given instance", nargs: 1, type: "string", default: null },
+		});
+	}],
+	handler: async function(args, control) {
+		if (!args.all && !args.master && !args.slave && !args.instance) {
+			logger.error("At least one of --all, --master, --slave and --instance must be passed");
+			process.exitCode = 1;
+			return;
+		}
+		let instance_ids = args.instance ? [await libCommand.resolveInstance(control, args.instance)] : [];
+		let slave_ids = args.slave ? [await libCommand.resolveSlave(control, args.slave)] : [];
+		await control.setLogSubscriptions({ all: args.all, master: args.master, slave_ids, instance_ids });
+		control.keepOpen = true;
+	},
+}));
+
+logCommands.add(new libCommand.Command({
+	definition: ["query", "Query cluster log", (yargs) => {
+		yargs.options({
+			"all": { describe: "Query the whole cluster log", nargs: 0, type: "boolean", default: false },
+			"master": { describe: "Query log of the master server", nargs: 0, type: "boolean", default: false },
+			"slave": { describe: "Query log of given slave", nargs: 1, type: "string", default: null },
+			"instance": { describe: "Query log of given instance", nargs: 1, type: "string", default: null },
+			"max-level": { describe: "Maximum log level to return", nargs: 1, type: "string", default: null },
+		});
+	}],
+	handler: async function(args, control) {
+		if (!args.all && !args.master && !args.slave && !args.instance) {
+			logger.error("At least one of --all, --master, --slave and --instance must be passed");
+			process.exitCode = 1;
+			return;
+		}
+		let instance_ids = args.instance ? [await libCommand.resolveInstance(control, args.instance)] : [];
+		let slave_ids = args.slave ? [await libCommand.resolveSlave(control, args.slave)] : [];
+		let result = await libLink.messages.queryLog.send(control, {
+			all: args.all,
+			master: args.master,
+			slave_ids,
+			instance_ids,
+			max_level: args.maxLevel,
+		});
+
+		let stdoutLogger = winston.createLogger({
+			level: "verbose",
+			levels,
+			format: new libLoggingUtils.TerminalFormat({ showTimestamp: true }),
+			transports: [
+				new ConsoleTransport({ errorLevels: [], warnLevels: [] }),
+			],
+		});
+		for (let info of result.log) {
+			stdoutLogger.log(info);
+		}
+	},
+}));
+
 const debugCommands = new libCommand.CommandTree({ name: "debug", description: "Debugging utilities" });
 debugCommands.add(new libCommand.Command({
 	definition: ["dump-ws", "Dump WebSocket messages sent and received by master", (yargs) => { }],
 	handler: async function(args, control) {
 		await libLink.messages.debugDumpWs.send(control);
-		return new Promise(() => {});
+		control.keepOpen = true;
 	},
 }));
 
@@ -519,6 +584,24 @@ class Control extends libLink.Link {
 		for (let controlPlugin of controlPlugins.values()) {
 			libPlugin.attachPluginMessages(this, controlPlugin.info, controlPlugin);
 		}
+
+		/**
+		 * Keep the control connection alive after the command completes.
+		 * @type {boolean}
+		 */
+		this.keepOpen = false;
+	}
+
+	async setLogSubscriptions({
+		all = false,
+		master = false,
+		slave_ids = [],
+		instance_ids = [],
+		max_level = null,
+	}) {
+		await libLink.messages.setLogSubscriptions.send(this, {
+			all, master, slave_ids, instance_ids, max_level,
+		});
 	}
 
 	async logMessageEventHandler(message) {
@@ -608,6 +691,7 @@ async function startControl() {
 	rootCommands.add(permissionCommands);
 	rootCommands.add(roleCommands);
 	rootCommands.add(userCommands);
+	rootCommands.add(logCommands);
 	rootCommands.add(debugCommands);
 
 	logger.verbose("Loading Plugin info");
@@ -704,12 +788,11 @@ async function startControl() {
 		});
 	});
 
-	let keepOpen = Boolean(args.keepOpen);
 	try {
 		await targetCommand.run(args, control);
 
 	} catch (err) {
-		keepOpen = false;
+		control.keepOpen = false;
 		if (err instanceof libErrors.CommandError) {
 			logger.error(`Error running command: ${err.message}`);
 			process.exitCode = 1;
@@ -723,7 +806,7 @@ async function startControl() {
 		}
 
 	} finally {
-		if (!keepOpen) {
+		if (!control.keepOpen) {
 			await control.shutdown();
 		}
 	}
diff --git a/packages/lib/link/messages.js b/packages/lib/link/messages.js
index 3b1a9b48..1eb28116 100644
--- a/packages/lib/link/messages.js
+++ b/packages/lib/link/messages.js
@@ -641,10 +641,41 @@ messages.setLogSubscriptions = new Request({
 	permission: "core.log.follow",
 	requestProperties: {
 		"all": { type: "boolean" },
+		"master": { type: "boolean" },
+		"slave_ids": {
+			type: "array",
+			items: { type: "integer" },
+		},
 		"instance_ids": {
 			type: "array",
 			items: { type: "integer" },
 		},
+		"max_level": { type: ["string", "null"] },
+	},
+});
+
+messages.queryLog = new Request({
+	type: "query_log",
+	links: ["control-master"],
+	permission: "core.log.query",
+	requestProperties: {
+		"all": { type: "boolean" },
+		"master": { type: "boolean" },
+		"slave_ids": {
+			type: "array",
+			items: { type: "integer" },
+		},
+		"instance_ids": {
+			type: "array",
+			items: { type: "integer" },
+		},
+		"max_level": { type: ["string", "null"] },
+	},
+	responseProperties: {
+		"log": {
+			type: "array",
+			items: { type: "object" },
+		},
 	},
 });
 
diff --git a/packages/lib/logging_utils.js b/packages/lib/logging_utils.js
index 26a554a8..990b2597 100644
--- a/packages/lib/logging_utils.js
+++ b/packages/lib/logging_utils.js
@@ -64,6 +64,11 @@ class TerminalFormat {
 
 	transform(info, options) {
 		info = this.colorize.transform(info, this.colorize.options);
+		let ts = "";
+		if (options.showTimestamp && info.timestamp) {
+			ts = `${info.timestamp.replace("T", " ")} `;
+		}
+
 		let src = " ";
 		if (info.instance_name) {
 			src += `i:${info.instance_name} `;
@@ -80,9 +85,9 @@ class TerminalFormat {
 		}
 
 		if (info.stack) {
-			info[MESSAGE] = `[${info.level}]${src}${info.stack}`;
+			info[MESSAGE] = `${ts}[${info.level}]${src}${info.stack}`;
 		} else {
-			info[MESSAGE] = `[${info.level}]${src}${info.message}`;
+			info[MESSAGE] = `${ts}[${info.level}]${src}${info.message}`;
 		}
 		return info;
 	}
diff --git a/packages/lib/users.js b/packages/lib/users.js
index 81097243..a55ef972 100644
--- a/packages/lib/users.js
+++ b/packages/lib/users.js
@@ -450,6 +450,11 @@ definePermission({
 	title: "Follow cluster log",
 	description: "Receive new entries in the cluster log.  Required to see instance console.",
 });
+definePermission({
+	name: "core.log.query",
+	title: "Query cluster log",
+	description: "Query past entries in the cluster log.  Required to see past entries in instance console.",
+});
 
 definePermission({
 	name: "core.debug.dump_ws",
diff --git a/packages/master/master.js b/packages/master/master.js
index b0cdeebe..caa02c01 100755
--- a/packages/master/master.js
+++ b/packages/master/master.js
@@ -562,6 +562,11 @@ class BaseConnection extends libLink.Link {
 	}
 }
 
+const lastQueryLogTime = new libPrometheus.Gauge(
+	"clusterio_master_last_query_log_duration_seconds",
+	"Time in seconds the last log query took to execute."
+);
+
 let controlConnections = [];
 class ControlConnection extends BaseConnection {
 	constructor(registerData, connector, user) {
@@ -586,6 +591,8 @@ class ControlConnection extends BaseConnection {
 		this.logTransport = null;
 		this.logSubscriptions = {
 			all: false,
+			master: false,
+			slave_ids: [],
 			instance_ids: [],
 		};
 
@@ -780,22 +787,37 @@ class ControlConnection extends BaseConnection {
 		this.updateLogSubscriptions();
 	}
 
+	static logFilter({ all, master, slave_ids, instance_ids, max_level }) {
+		return info => {
+			// Note: reversed to filter out undefined levels
+			if (max_level && !(levels[info.level] <= levels[max_level])) {
+				return false;
+			}
+
+			if (all) {
+				return true;
+			}
+			if (master && info.slave_id === undefined) {
+				return true;
+			}
+			if (info.slave_id && slave_ids.includes(info.slave_id)) {
+				return true;
+			}
+			if (info.instance_id && instance_ids.includes(info.instance_id)) {
+				return true;
+			}
+			return false;
+		};
+	}
+
 	updateLogSubscriptions() {
-		if (this.logSubscriptions.all || this.logSubscriptions.instance_ids.length) {
+		let { all, master, slave_ids, instance_ids } = this.logSubscriptions;
+		if (all || master || slave_ids.length || instance_ids.length) {
 			if (!this.logTransport) {
 				this.logTransport = new libLoggingUtils.LinkTransport({ link: this });
 				clusterLogger.add(this.logTransport);
 			}
-			if (this.logSubscriptions.all) {
-				this.logTransport.filter = null;
-			} else {
-				this.logTransport.filter = info => {
-					if (info.instance_id && this.logSubscriptions.instance_ids.includes(info.instance_id)) {
-						return true;
-					}
-					return false;
-				};
-			}
+			this.logTransport.filter = this.constructor.logFilter(this.logSubscriptions);
 
 		} else if (this.logTransport) {
 			clusterLogger.remove(this.logTransport);
@@ -803,6 +825,36 @@ class ControlConnection extends BaseConnection {
 		}
 	}
 
+	async queryLogRequestHandler(message) {
+		let transport = new winston.transports.File({ filename: "cluster.log" });
+		let query = util.promisify((options, callback) => transport.query(options, callback));
+
+		// Available options and defaults inferred from reading the source
+		// rows: number = limit || 10
+		// limit: number // alias of rows.
+		// start: number = 0
+		// until: Date = now
+		// from: Date = until - 24h
+		// order: "asc"|"desc" = "desc"
+		// fields: Array<string>
+		// level: string
+		// This interface is junk:
+		// - The level option filters by exact match
+		// - No way to add your own filter
+		// - No way to stream results
+		// - The log file is read starting from the beginning
+		let setDuration = lastQueryLogTime.startTimer();
+		let log = await query({
+			order: "asc",
+			limit: Infinity,
+			from: new Date(0),
+		});
+
+		log = log.filter(this.constructor.logFilter(message.data));
+		setDuration();
+		return { log };
+	}
+
 	async listPermissionsRequestHandler(message) {
 		let list = [];
 		for (let permission of libUsers.permissions.values()) {
diff --git a/packages/web_ui/src/util/websocket.jsx b/packages/web_ui/src/util/websocket.jsx
index 1805cc8a..f3de0e4d 100644
--- a/packages/web_ui/src/util/websocket.jsx
+++ b/packages/web_ui/src/util/websocket.jsx
@@ -107,7 +107,10 @@ export class Control extends libLink.Link {
 	async updateLogSubscriptions() {
 		await libLink.messages.setLogSubscriptions.send(this, {
 			all: false,
+			master: false,
+			slave_ids: [],
 			instance_ids: [...this.instanceLogHandlers.keys()],
+			max_level: null,
 		});
 	}