diff --git a/SQLBackupToCOS/BackupService.cs b/SQLBackupToCOS/BackupService.cs
index c518942..3ee94cf 100644
--- a/SQLBackupToCOS/BackupService.cs
+++ b/SQLBackupToCOS/BackupService.cs
@@ -1,10 +1,11 @@
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
-using SQLBackupToCOS;
 using System.Diagnostics;
 using System.Text;
 
+namespace SQLBackupToCOS;
+
 public class BackupService(ILogger<BackupService> logger, IConfiguration config, COSService cosService) : BackgroundService
 {
     private readonly ILogger<BackupService> _logger = logger;
@@ -39,6 +40,7 @@ public class BackupService(ILogger<BackupService> logger, IConfiguration config,
 
     private async Task RunOnceAsync(CancellationToken ct)
     {
+        var extraDir = _config.GetValue<string>("extraDir") ?? "/needBackup";
         var url = _config.GetValue<string>("Database:Host") ?? "172.17.0.1";
         var user = _config.GetValue<string>("Database:User") ?? "backupUser";
         var password = _config.GetValue<string>("Database:Password") ?? "";
@@ -49,7 +51,6 @@ public class BackupService(ILogger<BackupService> logger, IConfiguration config,
         var timestamp = DateTime.Now.ToString("yyyyMMddHHmmss");
         var dumpDir = $"/data/dumps/dump-{timestamp}";
         var finalDump = $"/data/dumps/dump-{timestamp}.tar.gz";
-        
         try
         {
             Directory.CreateDirectory(dumpDir);
@@ -91,7 +92,8 @@ public class BackupService(ILogger<BackupService> logger, IConfiguration config,
             }
 
             _logger.LogInformation("Compressing backup directory to {File}", finalDump);
-            await CompressDirectoryAsync(dumpDir, finalDump, ct);
+            
+            await CompressDirectoryAsync([dumpDir, extraDir], finalDump, ct);
             
             Directory.Delete(dumpDir, recursive: true);
             _logger.LogInformation("Backup completed: {File}", finalDump);
@@ -105,18 +107,37 @@ public class BackupService(ILogger<BackupService> logger, IConfiguration config,
         }
     }
 
-    private async Task CompressDirectoryAsync(string sourceDir, string targetFile, CancellationToken ct)
+    private async Task CompressDirectoryAsync(string[] sourceDirs, string targetFile, CancellationToken ct)
     {
-        // 使用 tar + gzip 压缩目录
+        // 构建 tar 命令参数
+        // tar -czf output.tar.gz -C /parent1 folder1 -C /parent2 folder2
+        var args = new StringBuilder($"-czf {targetFile}");
+        
+        foreach (var sourceDir in sourceDirs)
+        {
+            if (Directory.Exists(sourceDir))
+            {
+                var parentDir = Path.GetDirectoryName(sourceDir);
+                var folderName = Path.GetFileName(sourceDir);
+                args.Append($" -C {parentDir} {folderName}");
+            }
+            else
+            {
+                _logger.LogWarning("Directory not found, skipping: {Dir}", sourceDir);
+            }
+        }
+
         var psi = new ProcessStartInfo
         {
             FileName = "tar",
-            Arguments = $"-czf {targetFile} -C {Path.GetDirectoryName(sourceDir)} {Path.GetFileName(sourceDir)}",
+            Arguments = args.ToString(),
             RedirectStandardError = true,
             UseShellExecute = false,
             CreateNoWindow = true,
         };
 
+        _logger.LogInformation("Running tar command: tar {Args}", args.ToString());
+
         using var proc = Process.Start(psi) ?? throw new InvalidOperationException("Failed to start tar");
         var stderrTask = ConsumeStreamToLoggerAsync(proc.StandardError, _logger, ct);
         await stderrTask;
diff --git a/SQLBackupToCOS/appsettings.json.sample b/SQLBackupToCOS/appsettings.json.sample
index e634b97..fe4fdd4 100644
--- a/SQLBackupToCOS/appsettings.json.sample
+++ b/SQLBackupToCOS/appsettings.json.sample
@@ -6,6 +6,7 @@
     }
   },
   "BackupIntervalMinutes": 60,
+  "extraDir": "EXTRAPATH",
   "Database": {
     "Host": "172.17.0.1",
     "User": "SQLUSER",
diff --git a/docker-compose.yml b/docker-compose.yml
index 04b42a5..d003016 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -15,3 +15,6 @@ services:
       COS__SecretKey: SECRETKEY
       COS__FilePath: PATH
       BackupIntervalMinutes: 1440
+      extraDir: EXTRAPATH
+    volumes:
+      - srcDir:EXTRAPATH/srcDir:ro