diff --git a/docs/configuration/config.md b/docs/configuration/config.md
index e1f50e65..3a57e065 100644
--- a/docs/configuration/config.md
+++ b/docs/configuration/config.md
@@ -36,7 +36,9 @@
     // retryTimes when error occurs in inserting datas
     "retryTimes": 0,
     // max open connections with each clickhouse node. default to 1.
-    "maxOpenConns": 1
+    "maxOpenConns": 1,
+    // native or http, if configured secure and http both, means support https. default to native.
+    "protocol": "native"
   },
 
   // Kafka config
@@ -50,6 +52,8 @@
         "sasl.mechanism":"GSSAPI",
         "sasl.jaas.config":"com.sun.security.auth.module.Krb5LoginModule required useKeyTab=true storeKey=true debug=true keyTab=\"/etc/security/mmmtest.keytab\" principal=\"mmm@ALANWANG.COM\";"
     },
+    // whether reset domain realm. if this option is true, domain realm will replaced by "hadoop.{toLower(GSSAPI.Realm)}:{port}", this feature is worked when clickhouse_sinker connect to HUAWEI MRS kerberos kafka.
+    "resetSaslRealm": false,
 
     // SSL
     "tls": {