diff --git a/src/main/java/net/geedge/asw/common/util/Constants.java b/src/main/java/net/geedge/asw/common/util/Constants.java
index f609987..42c2707 100644
--- a/src/main/java/net/geedge/asw/common/util/Constants.java
+++ b/src/main/java/net/geedge/asw/common/util/Constants.java
@@ -75,4 +75,6 @@ public class Constants {
 	public static final String ENV_API_WEBSOCKET_PATH = "/api/v1/env/websocket";
 
 	public static final String ENV_API_TCPDUMP_PATH = "/api/v1/env/pcap";
+
+	public static final String EMPTY_FILE_MD5 = "d41d8cd98f00b204e9800998ecf8427e";
 }
diff --git a/src/main/java/net/geedge/asw/module/environment/controller/EnvironmentController.java b/src/main/java/net/geedge/asw/module/environment/controller/EnvironmentController.java
index e8025f7..f088327 100644
--- a/src/main/java/net/geedge/asw/module/environment/controller/EnvironmentController.java
+++ b/src/main/java/net/geedge/asw/module/environment/controller/EnvironmentController.java
@@ -1,7 +1,8 @@
 package net.geedge.asw.module.environment.controller;
 
 import cn.dev33.satoken.stp.StpUtil;
-import cn.hutool.core.util.ObjectUtil;
+import cn.hutool.core.io.FileUtil;
+import cn.hutool.core.util.ArrayUtil;
 import cn.hutool.http.HttpRequest;
 import cn.hutool.http.HttpResponse;
 import cn.hutool.json.JSONObject;
@@ -164,11 +165,10 @@ public class EnvironmentController {
 
 
     @DeleteMapping("/{envId}/session/{sessionId}/pcap/{pcapId}")
-    public void stopTcpdump(@PathVariable("envId") String envId,
+    public R stopTcpdump(@PathVariable("envId") String envId,
                          @PathVariable("sessionId") String sessionId,
                          @PathVariable("pcapId") String pcapId,
-                         @RequestParam Map param,
-                         HttpServletResponse response) throws IOException, ServletException {
+                         @RequestParam Map param) throws IOException, ServletException {
         EnvironmentSessionEntity session = environmentSessionService.getOne(new LambdaQueryWrapper<EnvironmentSessionEntity>().eq(EnvironmentSessionEntity::getId, sessionId).eq(EnvironmentSessionEntity::getStatus, 1));
         if (T.ObjectUtil.isNull(session)){
             throw new ASWException(RCode.ENVIRONMENT_SESSION_NOT_EXIST);
@@ -178,7 +178,7 @@ public class EnvironmentController {
             throw new ASWException(RCode.ENVIRONMENT_NOT_EXIST);
         }
         // build query param
-        Map params = T.MapUtil.builder().put("id", pcapId).put("returnFile", true).build();
+        Map params = T.MapUtil.builder().put("id", pcapId).put("returnFile", T.MapUtil.getBool(param, "savePcap")).build();
         ResponseEntity<byte[]> responseEntity = EnvironmentUtil.stopTcpdump(environment, params);
         if (T.MapUtil.getBool(param, "savePcap")){
             // save pcap to workspace
@@ -189,10 +189,12 @@ public class EnvironmentController {
                 String formatTime = new SimpleDateFormat("yyyyMMddHHmmss").format(new Date());
                 destination = T.FileUtil.file(T.WebPathUtil.getRootPath(), workspace.getId(), T.StrUtil.concat(true, pcapName, "-", formatTime, ".pcap"));
             }
-            FileOutputStream fos = new FileOutputStream(destination);
-            fos.write(responseEntity.getBody());
-            fos.flush();
-            fos.close();
+            // create empty file
+            destination = FileUtil.touch(destination);
+           if (ArrayUtil.isNotEmpty(responseEntity.getBody())){
+               FileOutputStream fos = new FileOutputStream(destination);
+               T.IoUtil.write(fos,true, responseEntity.getBody());
+           }
             log.info("save pcap to path:{}", destination.getAbsolutePath());
             // save entity
             PcapEntity entity = new PcapEntity();
@@ -204,12 +206,9 @@ public class EnvironmentController {
             entity.setCreateUserId(StpUtil.getLoginIdAsString());
             entity.setWorkspaceId(workspace.getId());
             entity.setPath(destination.getPath());
-            entity.setMd5(T.DigestUtil.md5Hex(destination));
-
+            entity.setMd5(destination.length() == 0 ? Constants.EMPTY_FILE_MD5 : T.DigestUtil.md5Hex(destination));
             pcapService.save(entity);
-            response.getWriter().write(T.JSONUtil.toJsonStr(R.ok()));
-        }else {
-            EnvironmentUtil.writeResponseWithHeaders(response, responseEntity);
         }
+        return R.ok();
     }
 }
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