diff --git a/gocron-node.go b/gocron-node.go
index 84eda20..163997e 100644
--- a/gocron-node.go
+++ b/gocron-node.go
@@ -9,7 +9,6 @@ import (
     "runtime"
     "os"
     "fmt"
-    "strings"
 )
 
 const AppVersion = "1.2"
@@ -18,12 +17,8 @@ func main()  {
 	var serverAddr string
     var allowRoot bool
     var version bool
-    var keyFile string
-    var certFile string
     flag.BoolVar(&allowRoot, "allow-root", false, "./gocron-node -allow-root")
     flag.StringVar(&serverAddr, "s", "0.0.0.0:5921", "./gocron-node -s ip:port")
-    flag.StringVar(&certFile, "cert-file", "", "./gocron-node -cert-file path")
-    flag.StringVar(&keyFile, "key-file", "", "./gocron-node -key-file path")
     flag.BoolVar(&version, "v", false, "./gocron-node -v")
     flag.Parse()
 
@@ -32,25 +27,11 @@ func main()  {
         os.Exit(0)
     }
 
-    certFile = strings.TrimSpace(certFile)
-    keyFile = strings.TrimSpace(keyFile)
-
-    if certFile != "" && keyFile == "" {
-        fmt.Println("missing argument key-file")
-        return
-    }
-
-    if keyFile != "" && certFile == "" {
-        fmt.Println("missing argument cert-file")
-        return
-    }
-
     if runtime.GOOS != "windows" && os.Getuid() == 0 && !allowRoot   {
         fmt.Println("Do not run gocron-node as root user")
         os.Exit(1)
     }
 
 
-
-	server.Start(serverAddr, certFile, keyFile)
+	server.Start(serverAddr)
 }
\ No newline at end of file
diff --git a/gocron.go b/gocron.go
index a9f60c5..cc58076 100644
--- a/gocron.go
+++ b/gocron.go
@@ -10,7 +10,7 @@ import (
     "github.com/ouqiang/gocron/cmd"
 )
 
-const AppVersion = "1.2"
+const AppVersion = "1.1"
 
 func main() {
     app := cli.NewApp()
diff --git a/models/host.go b/models/host.go
index 0066607..cd13247 100644
--- a/models/host.go
+++ b/models/host.go
@@ -10,7 +10,6 @@ type Host struct {
     Name      string    `xorm:"varchar(64) notnull"`             // 主机名称
     Alias     string    `xorm:"varchar(32) notnull default '' "`  // 主机别名
     Port      int       `xorm:"notnull default 22"`               // 主机端口
-    CertFile  string    `xorm:"varchar(64) notnull default '' "`
     Remark    string    `xorm:"varchar(100) notnull default '' "` // 备注
     BaseModel       `xorm:"-"`
     Selected bool   `xorm:"-"`
@@ -27,7 +26,7 @@ func (host *Host) Create() (insertId int16, err error) {
 }
 
 func (host *Host) UpdateBean(id int16) (int64, error)  {
-    return Db.ID(id).Cols("name,alias,port,cert_file,remark").Update(host)
+    return Db.ID(id).Cols("name,alias,port,remark").Update(host)
 }
 
 
diff --git a/models/migration.go b/models/migration.go
index c9d085c..ee186ea 100644
--- a/models/migration.go
+++ b/models/migration.go
@@ -49,10 +49,9 @@ func isDatabaseExist(name string) bool {
 
 // 迭代升级数据库, 新建表、新增字段等
 func (migration *Migration) Upgrade(oldVersionId int)  {
-    versionIds   := []int{110, 120}
+    versionIds   := []int{110}
     upgradeFuncs := []func(*xorm.Session) error {
         migration.upgradeFor110,
-        migration.upgradeFor120,
     }
 
     // 默认当前版本为v1.0
@@ -136,13 +135,3 @@ func (migration *Migration) upgradeFor110(session *xorm.Session) error {
 
     return err
 }
-
-
-// 升级到v1.2版本
-func (migration *Migration) upgradeFor120(session *xorm.Session) error {
-    // host表增加cert_file字段
-    tableName := TablePrefix + "host"
-    _, err := session.Exec(fmt.Sprintf("ALTER TABLE %s Add COLUMN cert_file VARCHAR(64) NOT NULL DEFAULT ''", tableName))
-
-    return err
-}
\ No newline at end of file
diff --git a/models/task_host.go b/models/task_host.go
index 10611fe..5d1015d 100644
--- a/models/task_host.go
+++ b/models/task_host.go
@@ -12,7 +12,6 @@ type TaskHostDetail struct {
     Name string
     Port int
     Alias string
-    CertFile string
 }
 
 func (TaskHostDetail) TableName() string  {
@@ -49,7 +48,7 @@ func (th *TaskHost) Add(taskId int, hostIds []int) error {
 
 func (th *TaskHost) GetHostIdsByTaskId(taskId int) ([]TaskHostDetail, error) {
     list := make([]TaskHostDetail, 0)
-    fields := "th.id,th.host_id,h.alias,h.name,h.port,h.cert_file"
+    fields := "th.id,th.host_id,h.alias,h.name,h.port"
     err := Db.Alias("th").
         Join("LEFT", hostTableName(), "th.host_id=h.id").
         Where("th.task_id = ?", taskId).
diff --git a/modules/rpc/client/client.go b/modules/rpc/client/client.go
index ca34e40..937459d 100644
--- a/modules/rpc/client/client.go
+++ b/modules/rpc/client/client.go
@@ -16,11 +16,11 @@ var (
     errUnavailable = errors.New("无法连接远程服务器")
 )
 
-func ExecWithRetry(ip string, port int, certFile string,taskReq *pb.TaskRequest) (string, error)  {
-    tryTimes := 15
+func ExecWithRetry(ip string, port int, taskReq *pb.TaskRequest) (string, error)  {
+    tryTimes := 60
     i := 0
     for i < tryTimes {
-        output, err := Exec(ip, port, certFile, taskReq)
+        output, err := Exec(ip, port, taskReq)
         if err != errUnavailable {
             return output, err
         }
@@ -31,14 +31,14 @@ func ExecWithRetry(ip string, port int, certFile string,taskReq *pb.TaskRequest)
     return "", errUnavailable
 }
 
-func Exec(ip string, port int, certFile string, taskReq *pb.TaskRequest) (string, error)  {
+func Exec(ip string, port int, taskReq *pb.TaskRequest) (string, error)  {
     defer func() {
        if err := recover(); err != nil {
            logger.Error("panic#rpc/client.go:Exec#", err)
        }
     } ()
     addr := fmt.Sprintf("%s:%d", ip, port)
-    conn, err := grpcpool.Pool.Get(addr, certFile)
+    conn, err := grpcpool.Pool.Get(addr)
     if err != nil {
         return "", err
     }
diff --git a/modules/rpc/grpcpool/grpc_pool.go b/modules/rpc/grpcpool/grpc_pool.go
index 7b73c18..ec08f4c 100644
--- a/modules/rpc/grpcpool/grpc_pool.go
+++ b/modules/rpc/grpcpool/grpc_pool.go
@@ -6,8 +6,6 @@ import (
     "time"
     "google.golang.org/grpc"
     "errors"
-    "google.golang.org/grpc/credentials"
-    "strings"
 )
 
 
@@ -32,12 +30,12 @@ type GRPCPool struct {
     sync.RWMutex
 }
 
-func (p *GRPCPool) Get(addr, certFile string) (*grpc.ClientConn, error)  {
+func (p *GRPCPool) Get(addr string) (*grpc.ClientConn, error)  {
     p.RLock()
     pool, ok := p.conns[addr]
     p.RUnlock()
     if !ok {
-        err := p.newCommonPool(addr, certFile)
+        err := p.newCommonPool(addr)
         if err != nil {
             return nil, err
         }
@@ -88,7 +86,7 @@ func (p *GRPCPool) ReleaseAll()  {
 }
 
 // 初始化底层连接池
-func (p *GRPCPool) newCommonPool(addr, certFile string) (error) {
+func (p *GRPCPool) newCommonPool(addr string) (error) {
     p.Lock()
     defer p.Unlock()
     commonPool, ok := p.conns[addr]
@@ -99,17 +97,7 @@ func (p *GRPCPool) newCommonPool(addr, certFile string) (error) {
         InitialCap: 1,
         MaxCap: 30,
         Factory: func() (interface{}, error) {
-            if certFile == "" {
-                return grpc.Dial(addr, grpc.WithInsecure())
-            }
-
-            server := strings.Split(addr, ":")
-            creds, err := credentials.NewClientTLSFromFile(certFile, server[0])
-            if err != nil {
-                return nil, err
-            }
-
-            return grpc.Dial(addr, grpc.WithTransportCredentials(creds))
+            return grpc.Dial(addr, grpc.WithInsecure())
         },
         Close: func(v interface{}) error {
             conn, ok := v.(*grpc.ClientConn)
diff --git a/modules/rpc/server/server.go b/modules/rpc/server/server.go
index 1bd9076..6f2a4d7 100644
--- a/modules/rpc/server/server.go
+++ b/modules/rpc/server/server.go
@@ -7,7 +7,6 @@ import (
     "google.golang.org/grpc"
     pb "github.com/ouqiang/gocron/modules/rpc/proto"
     "github.com/ouqiang/gocron/modules/utils"
-    "google.golang.org/grpc/credentials"
 )
 
 type Server struct {}
@@ -30,7 +29,7 @@ func (s Server) Run(ctx context.Context, req *pb.TaskRequest) (*pb.TaskResponse,
     return resp, nil
 }
 
-func Start(addr, certFile, keyFile string)  {
+func Start(addr string)  {
     defer func() {
        if err := recover(); err != nil {
            grpclog.Println("panic", err)
@@ -40,23 +39,9 @@ func Start(addr, certFile, keyFile string)  {
     if err != nil {
         grpclog.Fatal(err)
     }
-
-    var s *grpc.Server
-    if certFile != "" {
-        // TLS认证
-        creds, err := credentials.NewServerTLSFromFile(certFile, keyFile)
-        if err != nil {
-            grpclog.Fatalf("Failed to generate credentials %v", err)
-        }
-
-        s = grpc.NewServer(grpc.Creds(creds))
-        pb.RegisterTaskServer(s, Server{})
-        grpclog.Printf("listen %s with TLS", addr)
-    } else {
-        s = grpc.NewServer()
-        pb.RegisterTaskServer(s, Server{})
-        grpclog.Println("listen ", addr)
-    }
+    s := grpc.NewServer()
+    pb.RegisterTaskServer(s, Server{})
+    grpclog.Println("listen ", addr)
     err = s.Serve(l)
     if err != nil {
         grpclog.Fatal(err)
diff --git a/routers/host/host.go b/routers/host/host.go
index f1dba67..9625df4 100644
--- a/routers/host/host.go
+++ b/routers/host/host.go
@@ -64,7 +64,6 @@ type HostForm struct {
     Name string `binding:"Required;MaxSize(64)"`
     Alias string `binding:"Required;MaxSize(32)"`
     Port int `binding:"Required;Range(1-65535)"`
-    CertFile string
     Remark string
 }
 
@@ -94,12 +93,6 @@ func Store(ctx *macaron.Context, form HostForm) string  {
     hostModel.Alias = strings.TrimSpace(form.Alias)
     hostModel.Port = form.Port
     hostModel.Remark = strings.TrimSpace(form.Remark)
-    hostModel.CertFile = strings.TrimSpace(form.CertFile)
-
-    if hostModel.CertFile != "" && !utils.FileExist(hostModel.CertFile) {
-        return json.CommonFailure("证书文件不存在或无权限访问")
-    }
-
     isCreate := false
     oldHostModel := new(models.Host)
     err = oldHostModel.Find(int(id))
@@ -107,7 +100,6 @@ func Store(ctx *macaron.Context, form HostForm) string  {
         return json.CommonFailure("主机不存在")
     }
 
-
     if id > 0 {
         _, err = hostModel.UpdateBean(id)
     } else {
@@ -120,7 +112,10 @@ func Store(ctx *macaron.Context, form HostForm) string  {
 
     if !isCreate {
         oldAddr := fmt.Sprintf("%s:%d", oldHostModel.Name, oldHostModel.Port)
-        grpcpool.Pool.Release(oldAddr)
+        newAddr := fmt.Sprintf("%s:%d", hostModel.Name, hostModel.Port)
+        if oldAddr != newAddr {
+            grpcpool.Pool.Release(oldAddr)
+        }
 
         taskModel := new(models.Task)
         tasks, err := taskModel.ActiveListByHostId(id)
@@ -180,7 +175,7 @@ func Ping(ctx *macaron.Context) string  {
     taskReq := &rpc.TaskRequest{}
     taskReq.Command = "echo hello"
     taskReq.Timeout = 10
-    output, err := client.Exec(hostModel.Name, hostModel.Port, hostModel.CertFile, taskReq)
+    output, err := client.Exec(hostModel.Name, hostModel.Port, taskReq)
     if err != nil {
         return json.CommonFailure("连接失败-" + err.Error() + " " + output, err)
     }
diff --git a/service/task.go b/service/task.go
index df3a966..1585d61 100644
--- a/service/task.go
+++ b/service/task.go
@@ -181,7 +181,7 @@ func (h *RPCHandler) Run(taskModel models.Task) (result string, err error)  {
     var resultChan chan TaskResult = make(chan TaskResult, len(taskModel.Hosts))
     for _, taskHost := range taskModel.Hosts {
         go func(th models.TaskHostDetail) {
-            output, err := rpcClient.ExecWithRetry(th.Name, th.Port, th.CertFile, taskRequest)
+            output, err := rpcClient.ExecWithRetry(th.Name, th.Port, taskRequest)
             var errorMessage string = ""
             if err != nil {
                 errorMessage = err.Error()
diff --git a/templates/host/host_form.html b/templates/host/host_form.html
index 5c547f3..16edf9d 100644
--- a/templates/host/host_form.html
+++ b/templates/host/host_form.html
@@ -36,15 +36,6 @@
                     </div>
                 </div>
             </div>
-            <div class="two fields">
-                <div class="field">
-                    <label>证书路径</label>
-                    <div class="ui small  input">
-                        <input type="text" name="cert_file" value="{{{.Host.CertFile}}}"
-                               placeholder="data/certs/server.pem">
-                    </div>
-                </div>
-            </div>
             <div class="two fields">
                 <div class="field">
                     <label>备注</label>
diff --git a/templates/host/index.html b/templates/host/index.html
index f181259..6505ac7 100644
--- a/templates/host/index.html
+++ b/templates/host/index.html
@@ -36,7 +36,6 @@
                 <th>主机名</th>
                 <th>别名</th>
                 <th>端口</th>
-                <th>证书</th>
                 <th>备注</th>
                 <th>操作</th>
             </tr>
@@ -48,7 +47,6 @@
                 <td>{{{.Name}}}</td>
                 <td>{{{.Alias}}}</td>
                 <td>{{{.Port}}}</td>
-                <td>{{{.CertFile}}}</td>
                 <td>{{{.Remark}}}</td>
                 <td class="operation">
                     <a class="ui purple button"  href="/host/edit/{{{.Id}}}">编辑</a>