cherry pick pingcap#3884 to release-1.1

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

pkg/manager/member/template.go

@@ -279,15 +279,27 @@ func RenderPumpStartScript(model *PumpStartScriptModel) (string, error) {
 }
 
 // tidbInitStartScriptTpl is the template string of tidb initializer start script
-var tidbInitStartScriptTpl = template.Must(template.New("tidb-init-start-script").Parse(`import os, MySQLdb
+var tidbInitStartScriptTpl = template.Must(template.New("tidb-init-start-script").Parse(`import os, sys, time, MySQLdb
 host = '{{ .ClusterName }}-tidb'
 permit_host = '{{ .PermitHost }}'
 port = 4000
+retry_count = 0
+for i in range(0, 10):
+    try:
 {{- if .TLS }}
-conn = MySQLdb.connect(host=host, port=port, user='root', charset='utf8mb4',connect_timeout=5, ssl={'ca': '{{ .CAPath }}', 'cert': '{{ .CertPath }}', 'key': '{{ .KeyPath }}'})
+        conn = MySQLdb.connect(host=host, port=port, user='root', charset='utf8mb4',connect_timeout=5, ssl={'ca': '{{ .CAPath }}', 'cert': '{{ .CertPath }}', 'key': '{{ .KeyPath }}'})
 {{- else }}
-conn = MySQLdb.connect(host=host, port=port, user='root', connect_timeout=5, charset='utf8mb4')
+        conn = MySQLdb.connect(host=host, port=port, user='root', connect_timeout=5, charset='utf8mb4')
 {{- end }}
+    except MySQLdb.OperationalError as e:
+        print(e)
+        retry_count += 1
+        time.sleep(1)
+        continue
+    break
+if retry_count == 10:
+    sys.exit(1)
+
 {{- if .PasswordSet }}
 password_dir = '/etc/tidb/password'
 for file in os.listdir(password_dir):