diff --git a/common/build.gradle b/common/build.gradle
index 52b6f97..966bfb7 100644
--- a/common/build.gradle
+++ b/common/build.gradle
@@ -1,6 +1,8 @@
 dependencies {
 	modImplementation "net.fabricmc:fabric-loader:${rootProject.fabric_loader_version}"
 	modApi "${rootProject.architectury_id}:architectury:${rootProject.architectury_version}"
+
+	implementation 'io.lettuce:lettuce-core:6.2.3.RELEASE'
 }
 
 architectury {
diff --git a/common/src/main/java/cn/zbx1425/third_party/data/redis/RedisChannelInterface.java b/common/src/main/java/cn/zbx1425/third_party/data/redis/RedisChannelInterface.java
new file mode 100644
index 0000000..a0106bd
--- /dev/null
+++ b/common/src/main/java/cn/zbx1425/third_party/data/redis/RedisChannelInterface.java
@@ -0,0 +1,78 @@
+package cn.zbx1425.third_party.data.redis;
+
+import io.lettuce.core.RedisClient;
+import io.lettuce.core.api.StatefulRedisConnection;
+import io.lettuce.core.pubsub.RedisPubSubAdapter;
+import io.lettuce.core.pubsub.StatefulRedisPubSubConnection;
+import io.lettuce.core.pubsub.api.async.RedisPubSubAsyncCommands;
+
+import java.util.Map;
+
+public class RedisChannelInterface {
+    public RedisChannelMessageQueue Queue = new RedisChannelMessageQueue();
+    private final StatefulRedisPubSubConnection<String, String> channel;
+
+    private final StatefulRedisConnection<String, String> instance;
+
+    private volatile boolean StartedListening = false;
+
+    public RedisChannelInterface(String URI) {
+        this.channel = RedisClient.create(URI).connectPubSub();
+        this.instance = RedisClient.create(URI).connect();
+    }
+
+    public String get(String Key) {
+        return this.instance.sync().get(Key);
+    }
+
+    public void set(String Key, String Value) {
+        this.instance.sync().set(Key, Value);
+    }
+
+    public void hset(String Key, Map<String, String> Value) {
+        this.instance.sync().hset(Key, Value);
+    }
+
+    public Map<String, String> hgetall(String Key) {
+        return this.instance.sync().hgetall(Key);
+    }
+
+    public void publish(String Channel, String Data) {
+        this.channel.sync().publish(Channel, Data);
+    }
+
+    public synchronized void recvChannel(String[] Channels) {
+        if (StartedListening) {
+            this.stop();
+        }
+
+        RedisPubSubAdapter<String, String> adapter = new RedisPubSubAdapter<>() {
+            @Override
+            public void message(String channel, String message) {
+                Queue.append(channel, message);
+            }
+        };
+
+        RedisPubSubAsyncCommands<String, String> command = this.channel.async();
+
+        command.subscribe(Channels);
+
+        this.channel.addListener(adapter);
+
+        while (StartedListening) {
+            Thread.onSpinWait();
+        }
+
+        this.channel.removeListener(adapter);
+    }
+
+    public void stop() {
+        this.StartedListening = false;
+    }
+
+    public void close() {
+        this.channel.close();
+        this.instance.close();
+    }
+
+}
diff --git a/common/src/main/java/cn/zbx1425/third_party/data/redis/RedisChannelMessageQueue.java b/common/src/main/java/cn/zbx1425/third_party/data/redis/RedisChannelMessageQueue.java
new file mode 100644
index 0000000..3be8088
--- /dev/null
+++ b/common/src/main/java/cn/zbx1425/third_party/data/redis/RedisChannelMessageQueue.java
@@ -0,0 +1,20 @@
+package cn.zbx1425.third_party.data.redis;
+
+import java.util.ArrayList;
+import java.util.List;
+
+//Todo: not implemented, even not a queue
+public class RedisChannelMessageQueue {
+    private List<String> CachedMessage = new ArrayList<String>();
+    public RedisChannelMessageQueue() {}
+
+    public synchronized void append(String Channel, String Data) {
+        CachedMessage.add(Channel+"#"+Data);
+    }
+
+    public synchronized String next() {
+        String ret = CachedMessage.get(0);
+        CachedMessage.remove(0);
+        return ret;
+    }
+}
diff --git a/common/src/main/java/cn/zbx1425/worldcomment/data/persist/CommentTable.java b/common/src/main/java/cn/zbx1425/worldcomment/data/persist/CommentTable.java
index 21a5b4a..003f71e 100644
--- a/common/src/main/java/cn/zbx1425/worldcomment/data/persist/CommentTable.java
+++ b/common/src/main/java/cn/zbx1425/worldcomment/data/persist/CommentTable.java
@@ -1,6 +1,7 @@
 package cn.zbx1425.worldcomment.data.persist;
 
 import cn.zbx1425.worldcomment.data.CommentEntry;
+import cn.zbx1425.worldcomment.data.synchronizer.*;
 import io.netty.buffer.Unpooled;
 import it.unimi.dsi.fastutil.longs.*;
 import it.unimi.dsi.fastutil.objects.ObjectIterator;
@@ -25,15 +26,24 @@ public class CommentTable {
     Map<UUID, List<CommentEntry>> playerIndex = new HashMap<>();
     Long2ObjectSortedMap<CommentEntry> timeIndex = new Long2ObjectAVLTreeMap<>(Comparator.reverseOrder());
 
-    public CommentTable(Database db) {
+    private final Synchronizer synchronizer;
+
+    public CommentTable(Database db, Synchronizer sync) {
         this.db = db;
+        this.synchronizer = sync;
+
+        try {
+            this.synchronizer.sync(db.basePath.resolve("region"));
+        } catch (IOException e) {
+            //Todo: seems need to do something here
+        }
+
     }
 
     public void load() throws IOException {
         regionIndex.clear();
         playerIndex.clear();
         timeIndex.clear();
-        if (db.isHost) {
             try {
                 Files.createDirectories(db.basePath.resolve("region"));
             } catch (FileAlreadyExistsException ignored) {
@@ -53,9 +63,6 @@ public void load() throws IOException {
                     }
                 }
             }
-        } else {
-
-        }
     }
 
     public void loadRegion(ResourceLocation dimension, long region, byte[] data, boolean fromFile) {
@@ -130,10 +137,8 @@ public void insert(CommentEntry newEntry) throws IOException {
 
                     }
                 }
-                Path targetFile = getLevelRegionPath(newEntry.level, newEntry.region);
-                try (FileOutputStream oStream = new FileOutputStream(targetFile.toFile(), true)) {
-                    newEntry.writeFileStream(oStream);
-                }
+
+                this.synchronizer.update(newEntry, getLevelRegionPath(newEntry.level, newEntry.region));
             }
             regionIndex.get(newEntry.level)
                     .computeIfAbsent(newEntry.region.toLong(), ignored -> new ArrayList<>())
@@ -151,14 +156,12 @@ public void update(CommentEntry newEntry) throws IOException {
             if (regionData == null) return;
             for (CommentEntry existingEntry : regionData) {
                 if (existingEntry.id == newEntry.id) {
+                    //Todo: refactor this
                     existingEntry.deleted = newEntry.deleted;
                     existingEntry.like = newEntry.like;
                     assert existingEntry.fileOffset > 0;
                     if (db.isHost) {
-                        Path targetFile = getLevelRegionPath(newEntry.level, newEntry.region);
-                        try (RandomAccessFile oStream = new RandomAccessFile(targetFile.toFile(), "rw")) {
-                            existingEntry.updateInFile(oStream);
-                        }
+                        this.synchronizer.update(existingEntry, getLevelRegionPath(newEntry.level, newEntry.region));
                     }
                 }
             }
diff --git a/common/src/main/java/cn/zbx1425/worldcomment/data/persist/Database.java b/common/src/main/java/cn/zbx1425/worldcomment/data/persist/Database.java
index fac07d0..2efd084 100644
--- a/common/src/main/java/cn/zbx1425/worldcomment/data/persist/Database.java
+++ b/common/src/main/java/cn/zbx1425/worldcomment/data/persist/Database.java
@@ -1,6 +1,7 @@
 package cn.zbx1425.worldcomment.data.persist;
 
 import cn.zbx1425.worldcomment.data.Snowflake;
+import cn.zbx1425.worldcomment.data.synchronizer.SingletonSynchronizer;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.world.level.storage.LevelResource;
 
@@ -21,7 +22,7 @@ public class Database {
     public Database(MinecraftServer server) {
         this.server = server;
         this.basePath = Path.of(server.getWorldPath(LevelResource.ROOT).toString(), "world-comment");
-        comments = new CommentTable(this);
+        comments = new CommentTable(this, new SingletonSynchronizer());
     }
 
     public void load() throws IOException {
diff --git a/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/Command.java b/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/Command.java
new file mode 100644
index 0000000..1c29a00
--- /dev/null
+++ b/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/Command.java
@@ -0,0 +1,31 @@
+package cn.zbx1425.worldcomment.data.synchronizer;
+
+public class Command {
+    public static final String COMMAND_CHANNEL = "WORLD_COMMENT_COMMAND_CHANNEL";
+
+
+    public static String DataKey(String ID) {
+        if (ID.isEmpty()) {
+            return "WORLD_COMMENT_DATA#ALL";
+        }
+
+        return "WORLD_COMMENT_DATA#"+ID;
+    }
+
+    public static String Request(String ID) {
+        if (ID.isEmpty()) {
+            return "REQUEST#ALL";
+        }
+
+        return "REQUEST#"+ID;
+    }
+
+    public static String Update(String ID) {
+        return "UPDATE#"+ID;
+    }
+
+    public static String Updated(String ID) {
+        return "UPDATED#"+ID;
+    }
+
+}
diff --git a/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/RedisSynchronizer.java b/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/RedisSynchronizer.java
new file mode 100644
index 0000000..f5fbfd9
--- /dev/null
+++ b/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/RedisSynchronizer.java
@@ -0,0 +1,163 @@
+package cn.zbx1425.worldcomment.data.synchronizer;
+
+import cn.zbx1425.third_party.data.redis.RedisChannelInterface;
+import cn.zbx1425.worldcomment.data.CommentEntry;
+import io.netty.buffer.Unpooled;
+import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.resources.ResourceLocation;
+
+import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.nio.file.FileAlreadyExistsException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.stream.Stream;
+
+public class RedisSynchronizer implements Synchronizer {
+
+    private final RedisChannelInterface redis;
+
+    private final boolean host;
+    public RedisSynchronizer(String URI, boolean host) {
+        this.redis = new RedisChannelInterface(URI);
+        this.host = host;
+    }
+
+    @Override
+    public void sync(Path path) throws IOException {
+        if (this.host) {
+            this.upload(path);
+        } else {
+            this.fetchAll(path);
+        }
+    }
+
+
+    @Override
+    public void update(CommentEntry entry, Path targetFile) throws IOException {
+        try (RandomAccessFile oStream = new RandomAccessFile(targetFile.toFile(), "rw")) {
+            entry.updateInFile(oStream);
+        }
+
+
+        if (this.host) {
+            this.redis.hset(
+                    Command.DataKey(""),
+                    new HashMap<String, String>(){{
+                        put(String.valueOf(entry.id), entry.toString());
+                    }});
+
+
+            this.redis.publish(
+                    Command.COMMAND_CHANNEL,
+                    Command.Updated(String.valueOf(entry.id)));
+
+        } else {
+            this.redis.set(Command.DataKey(
+                            String.valueOf(entry.id)),
+                    entry.toString());
+
+            this.redis.publish(
+                    Command.COMMAND_CHANNEL,
+                    Command.Update(String.valueOf(entry.id)));
+        }
+    }
+
+    private void upload(Path dirPath) throws IOException {
+        HashMap<String, String> pendingUpload = new HashMap<>();
+
+        try {
+            Files.createDirectories(dirPath);
+        } catch (FileAlreadyExistsException ignored) {
+
+        }
+        try (Stream<Path> levelFiles = Files.list(dirPath)) {
+            for (Path levelPath : levelFiles.toList()) {
+                ResourceLocation dimension = new ResourceLocation(levelPath.getFileName().toString().replace("+", ":"));
+                try (Stream<Path> files = Files.list(levelPath)) {
+                    for (Path file : files.toList()) {
+                        String[] fileNameParts = file.getFileName().toString().split("\\.");
+                        if (fileNameParts.length != 4 || !fileNameParts[3].equals("bin")) continue;
+                        byte[] data = Files.readAllBytes(file);
+                        FriendlyByteBuf src = new FriendlyByteBuf(Unpooled.wrappedBuffer(data));
+                        while (src.readerIndex() < data.length) {
+                            CommentEntry entry = new CommentEntry(dimension, src, false);
+                            pendingUpload.put(String.valueOf(entry.id), entry.toString());
+                        }
+                    }
+                }
+            }
+        }
+
+        this.redis.hset(
+                Command.DataKey(""),
+                pendingUpload
+        );
+
+    }
+
+    private Map<String, String> fetchAll(Path dirPath) throws IOException {
+        Map<String, String> exist = this.redis.hgetall(Command.DataKey(""));
+
+        try {
+            Files.createDirectories(dirPath);
+        } catch (FileAlreadyExistsException ignored) {
+
+        }
+        try (Stream<Path> levelFiles = Files.list(dirPath)) {
+            for (Path levelPath : levelFiles.toList()) {
+                ResourceLocation dimension = new ResourceLocation(levelPath.getFileName().toString().replace("+", ":"));
+                try (Stream<Path> files = Files.list(levelPath)) {
+                    for (Path file : files.toList()) {
+                        String[] fileNameParts = file.getFileName().toString().split("\\.");
+                        if (fileNameParts.length != 4 || !fileNameParts[3].equals("bin")) continue;
+                        byte[] data = Files.readAllBytes(file);
+                        FriendlyByteBuf src = new FriendlyByteBuf(Unpooled.wrappedBuffer(data));
+                        while (src.readerIndex() < data.length) {
+                            CommentEntry entry = new CommentEntry(dimension, src, false);
+                            exist.remove(String.valueOf(entry.id));
+                        }
+                    }
+                }
+            }
+        }
+
+        exist.forEach((id, entry) -> {
+            CommentEntry commentEntry = new CommentEntry();
+            this.update(commentEntry, getLevelRegionPath(commentEntry.level, commentEntry.region));
+        });
+
+
+        //cache cleaned or some other situation
+        if (false) {
+            sendFetchCommand();
+        }
+    }
+
+    private void sendFetchCommand() {
+        this.redis.publish(
+                Command.COMMAND_CHANNEL,
+                Command.Request("")
+        );
+    }
+
+    public class receiver extends Thread {
+        @Override
+        public void run() {
+            redis.recvChannel(new String[]{Command.COMMAND_CHANNEL});
+
+            //todo: set queue handler will be better?
+            while (true) {
+                String command = redis.Queue.next();
+
+                if (command.) {
+                    continue;
+                }
+            }
+
+        }
+    }
+
+}
diff --git a/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/SingletonSynchronizer.java b/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/SingletonSynchronizer.java
new file mode 100644
index 0000000..4c5dfa4
--- /dev/null
+++ b/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/SingletonSynchronizer.java
@@ -0,0 +1,24 @@
+package cn.zbx1425.worldcomment.data.synchronizer;
+
+import cn.zbx1425.worldcomment.data.CommentEntry;
+
+import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.nio.file.Path;
+
+//Todo: doing nothing currently
+public class SingletonSynchronizer implements Synchronizer {
+
+
+    @Override
+    public void sync(Path path) throws IOException {
+        //do nothing
+    }
+
+    @Override
+    public void update(CommentEntry entry, Path targetFile) throws IOException {
+        try (RandomAccessFile oStream = new RandomAccessFile(targetFile.toFile(), "rw")) {
+            entry.updateInFile(oStream);
+        }
+    }
+}
diff --git a/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/Synchronizer.java b/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/Synchronizer.java
new file mode 100644
index 0000000..69db911
--- /dev/null
+++ b/common/src/main/java/cn/zbx1425/worldcomment/data/synchronizer/Synchronizer.java
@@ -0,0 +1,13 @@
+package cn.zbx1425.worldcomment.data.synchronizer;
+
+import cn.zbx1425.worldcomment.data.CommentEntry;
+
+import java.io.IOException;
+import java.nio.file.Path;
+
+public interface Synchronizer {
+
+    void sync(Path path) throws IOException;
+
+    void update(CommentEntry newEntry, Path targetFile) throws IOException;
+}