diff --git a/src/sf_proto.c b/src/sf_proto.c
index 4298c7a..ec9a02c 100644
--- a/src/sf_proto.c
+++ b/src/sf_proto.c
@@ -296,6 +296,10 @@ const char *sf_get_cmd_caption(const int cmd)
             return "REPORT_REQ_RECEIPT_REQ";
         case SF_SERVICE_PROTO_REPORT_REQ_RECEIPT_RESP:
             return "REPORT_REQ_RECEIPT_RESP";
+        case SF_SERVICE_PROTO_GET_GROUP_SERVERS_REQ:
+            return "GET_GROUP_SERVERS_REQ";
+        case SF_SERVICE_PROTO_GET_GROUP_SERVERS_RESP:
+            return "GET_GROUP_SERVERS_RESP";
         default:
             return "UNKOWN";
     }
diff --git a/src/sf_proto.h b/src/sf_proto.h
index c7fa838..d20d771 100644
--- a/src/sf_proto.h
+++ b/src/sf_proto.h
@@ -27,6 +27,10 @@
 #include "sf_types.h"
 #include "sf_util.h"
 
+//for connection manager
+#define SF_SERVICE_PROTO_GET_GROUP_SERVERS_REQ    111
+#define SF_SERVICE_PROTO_GET_GROUP_SERVERS_RESP   112
+
 #define SF_PROTO_ACK                    116
 
 #define SF_PROTO_ACTIVE_TEST_REQ        117
@@ -89,6 +93,20 @@ typedef struct sf_common_proto_header {
     char padding[3];
 } SFCommonProtoHeader;
 
+typedef struct sf_proto_get_group_servers_req {
+    char group_id[4];
+} SFProtoGetGroupServersReq;
+
+typedef struct sf_proto_get_group_servers_resp_body_header {
+    char count[2];
+} SFProtoGetGroupServersRespBodyHeader;
+
+typedef struct sf_proto_get_group_servers_resp_body_part {
+    char is_master;
+    char is_active;
+    char server_id[4];
+} SFProtoGetGroupServersRespBodyPart;
+
 typedef struct sf_proto_idempotency_additional_header {
     char req_id[8];
 } SFProtoIdempotencyAdditionalHeader;