diff --git a/pkg/filesystem/file.go b/pkg/filesystem/file.go
index 72e8cfb..1113441 100644
--- a/pkg/filesystem/file.go
+++ b/pkg/filesystem/file.go
@@ -3,6 +3,7 @@ package filesystem
 import (
 	"context"
 	model "github.com/HFO4/cloudreve/models"
+	"github.com/HFO4/cloudreve/pkg/conf"
 	"github.com/HFO4/cloudreve/pkg/filesystem/fsctx"
 	"github.com/HFO4/cloudreve/pkg/filesystem/response"
 	"github.com/HFO4/cloudreve/pkg/serializer"
@@ -230,13 +231,13 @@ func (fs *FileSystem) GetDownloadURL(ctx context.Context, path string, timeout s
 // GetSource 获取可直接访问文件的外链地址
 func (fs *FileSystem) GetSource(ctx context.Context, fileID uint) (string, error) {
 	// 查找文件记录
-	fileObject, err := model.GetFilesByIDs([]uint{fileID}, fs.User.ID)
-	if err != nil || len(fileObject) == 0 {
+	err := fs.resetFileIDIfNotExist(ctx, fileID)
+	if err != nil {
 		return "", ErrObjectNotExist.WithError(err)
 	}
 
 	// 检查存储策略是否可以获得外链
-	if !fileObject[0].GetPolicy().IsOriginLinkEnable {
+	if !fs.Policy.IsOriginLinkEnable {
 		return "", serializer.NewError(
 			serializer.CodePolicyNotAllowed,
 			"当前存储策略无法获得外链",
@@ -244,7 +245,7 @@ func (fs *FileSystem) GetSource(ctx context.Context, fileID uint) (string, error
 		)
 	}
 
-	source, err := fs.signURL(ctx, &fileObject[0], 0, false)
+	source, err := fs.signURL(ctx, &fs.FileTarget[0], 0, false)
 	if err != nil {
 		return "", serializer.NewError(serializer.CodeNotSet, "无法获取外链", err)
 	}
@@ -307,6 +308,12 @@ func (fs *FileSystem) resetPolicyToFirstFile(ctx context.Context) error {
 	if len(fs.FileTarget) == 0 {
 		return ErrObjectNotExist
 	}
+
+	// 从机模式不进行操作
+	if conf.SystemConfig.Mode == "slave" {
+		return nil
+	}
+
 	fs.Policy = fs.FileTarget[0].GetPolicy()
 	err := fs.dispatchHandler()
 	if err != nil {
diff --git a/pkg/filesystem/file_test.go b/pkg/filesystem/file_test.go
index 7394cc9..bdc377a 100644
--- a/pkg/filesystem/file_test.go
+++ b/pkg/filesystem/file_test.go
@@ -277,13 +277,13 @@ func TestFileSystem_deleteGroupedFile(t *testing.T) {
 func TestFileSystem_GetSource(t *testing.T) {
 	asserts := assert.New(t)
 	ctx := context.Background()
-	fs := FileSystem{
-		User: &model.User{Model: gorm.Model{ID: 1}},
-	}
 	auth.General = auth.HMACAuth{SecretKey: []byte("123")}
 
 	// 正常
 	{
+		fs := FileSystem{
+			User: &model.User{Model: gorm.Model{ID: 1}},
+		}
 		// 清空缓存
 		err := cache.Deletes([]string{"siteURL"}, "setting_")
 		asserts.NoError(err)
@@ -312,6 +312,9 @@ func TestFileSystem_GetSource(t *testing.T) {
 
 	// 文件不存在
 	{
+		fs := FileSystem{
+			User: &model.User{Model: gorm.Model{ID: 1}},
+		}
 		// 清空缓存
 		err := cache.Deletes([]string{"siteURL"}, "setting_")
 		asserts.NoError(err)
@@ -332,6 +335,9 @@ func TestFileSystem_GetSource(t *testing.T) {
 
 	// 未知上传策略
 	{
+		fs := FileSystem{
+			User: &model.User{Model: gorm.Model{ID: 1}},
+		}
 		// 清空缓存
 		err := cache.Deletes([]string{"siteURL"}, "setting_")
 		asserts.NoError(err)
@@ -358,6 +364,9 @@ func TestFileSystem_GetSource(t *testing.T) {
 
 	// 不允许获取外链
 	{
+		fs := FileSystem{
+			User: &model.User{Model: gorm.Model{ID: 1}},
+		}
 		// 清空缓存
 		err := cache.Deletes([]string{"siteURL"}, "setting_")
 		asserts.NoError(err)
diff --git a/pkg/filesystem/filesystem.go b/pkg/filesystem/filesystem.go
index 085ad4e..1a867bb 100644
--- a/pkg/filesystem/filesystem.go
+++ b/pkg/filesystem/filesystem.go
@@ -144,7 +144,6 @@ func (fs *FileSystem) dispatchHandler() error {
 		currentPolicy = fs.Policy
 	}
 
-	// 根据存储策略类型分配适配器
 	switch policyType {
 	case "mock":
 		return nil
diff --git a/pkg/filesystem/remote/handler.go b/pkg/filesystem/remote/handler.go
index 353655e..e75a7b2 100644
--- a/pkg/filesystem/remote/handler.go
+++ b/pkg/filesystem/remote/handler.go
@@ -106,7 +106,7 @@ func (handler Handler) Thumb(ctx context.Context, path string) (*response.Conten
 	sourcePath := base64.RawURLEncoding.EncodeToString([]byte(path))
 	thumbURL := handler.getAPI("thumb") + "/" + sourcePath
 	ttl := model.GetIntSetting("slave_api_timeout", 60)
-	signedThumbURL, err := auth.SignURI(handler.AuthInstance, thumbURL, int64(ttl))
+	signedThumbURL, err := auth.SignURI(handler.AuthInstance, thumbURL, time.Now().Unix()+int64(ttl))
 	if err != nil {
 		return nil, err
 	}
diff --git a/routers/controllers/file.go b/routers/controllers/file.go
index 502e7ea..21e10b2 100644
--- a/routers/controllers/file.go
+++ b/routers/controllers/file.go
@@ -11,7 +11,6 @@ import (
 	"github.com/HFO4/cloudreve/pkg/util"
 	"github.com/HFO4/cloudreve/service/explorer"
 	"github.com/gin-gonic/gin"
-	"io"
 	"net/http"
 	"net/url"
 	"strconv"
@@ -130,12 +129,9 @@ func Thumb(c *gin.Context) {
 		c.Redirect(http.StatusMovedPermanently, resp.URL)
 		return
 	}
-	http.ServeContent(c.Writer, c.Request, "thumb.png", fs.FileTarget[0].UpdatedAt, resp.Content)
 
-	// 检查是否需要关闭文件
-	if fc, ok := resp.Content.(io.Closer); ok {
-		defer fc.Close()
-	}
+	defer resp.Content.Close()
+	http.ServeContent(c.Writer, c.Request, "thumb.png", fs.FileTarget[0].UpdatedAt, resp.Content)
 
 }
 
diff --git a/service/explorer/file.go b/service/explorer/file.go
index 1e1215e..d6bb7fa 100644
--- a/service/explorer/file.go
+++ b/service/explorer/file.go
@@ -388,5 +388,16 @@ func (service *SlaveFileService) Thumb(ctx context.Context, c *gin.Context) seri
 	if err != nil {
 		return serializer.ParamErr("无法解析的文件地址", err)
 	}
+	fs.FileTarget = []model.File{{SourceName: string(fileSource), PicInfo: "1,1"}}
 
+	// 获取缩略图
+	resp, err := fs.GetThumb(ctx, 0)
+	if err != nil {
+		return serializer.Err(serializer.CodeNotSet, "无法获取缩略图", err)
+	}
+
+	defer resp.Content.Close()
+	http.ServeContent(c.Writer, c.Request, "thumb.png", time.Now(), resp.Content)
+
+	return serializer.Response{Code: 0}
 }