diff --git a/include/util/taoserror.h b/include/util/taoserror.h
index 142427ca6b24f130dd8cd73c22dd586036891f85..a709ccf10c98f2753b11e77946306c9e9a750106 100644
--- a/include/util/taoserror.h
+++ b/include/util/taoserror.h
@@ -539,20 +539,20 @@ int32_t* taosGetErrno();
 // #define TSDB_CODE_SYN_INVALID_CHECKSUM       TAOS_DEF_ERROR_CODE(0, 0x0908) // 2.x
 // #define TSDB_CODE_SYN_INVALID_MSGLEN         TAOS_DEF_ERROR_CODE(0, 0x0909) // 2.x
 // #define TSDB_CODE_SYN_INVALID_MSGTYPE        TAOS_DEF_ERROR_CODE(0, 0x090A) // 2.x
-#define TSDB_CODE_SYN_IS_LEADER                 TAOS_DEF_ERROR_CODE(0, 0x090B)
+// #define TSDB_CODE_SYN_IS_LEADER              TAOS_DEF_ERROR_CODE(0, 0x090B) // unused
 #define TSDB_CODE_SYN_NOT_LEADER                TAOS_DEF_ERROR_CODE(0, 0x090C)
-#define TSDB_CODE_SYN_ONE_REPLICA               TAOS_DEF_ERROR_CODE(0, 0x090D)
-#define TSDB_CODE_SYN_NOT_IN_NEW_CONFIG         TAOS_DEF_ERROR_CODE(0, 0x090E)
-#define TSDB_CODE_SYN_NEW_CONFIG_ERROR          TAOS_DEF_ERROR_CODE(0, 0x090F)  // internal
-#define TSDB_CODE_SYN_RECONFIG_NOT_READY        TAOS_DEF_ERROR_CODE(0, 0x0910)
+// #define TSDB_CODE_SYN_ONE_REPLICA            TAOS_DEF_ERROR_CODE(0, 0x090D) // unused
+// #define TSDB_CODE_SYN_NOT_IN_NEW_CONFIG      TAOS_DEF_ERROR_CODE(0, 0x090E) // unused
+#define TSDB_CODE_SYN_NEW_CONFIG_ERROR          TAOS_DEF_ERROR_CODE(0, 0x090F) // internal
+// #define TSDB_CODE_SYN_RECONFIG_NOT_READY     TAOS_DEF_ERROR_CODE(0, 0x0910) // unused
 #define TSDB_CODE_SYN_PROPOSE_NOT_READY         TAOS_DEF_ERROR_CODE(0, 0x0911)
-#define TSDB_CODE_SYN_STANDBY_NOT_READY         TAOS_DEF_ERROR_CODE(0, 0x0912)
-#define TSDB_CODE_SYN_BATCH_ERROR               TAOS_DEF_ERROR_CODE(0, 0x0913)
+// #define TSDB_CODE_SYN_STANDBY_NOT_READY      TAOS_DEF_ERROR_CODE(0, 0x0912) // unused
+// #define TSDB_CODE_SYN_BATCH_ERROR            TAOS_DEF_ERROR_CODE(0, 0x0913) // unused
 #define TSDB_CODE_SYN_RESTORING                 TAOS_DEF_ERROR_CODE(0, 0x0914)
-#define TSDB_CODE_SYN_INVALID_SNAPSHOT_MSG      TAOS_DEF_ERROR_CODE(0, 0x0915)  // internal
+#define TSDB_CODE_SYN_INVALID_SNAPSHOT_MSG      TAOS_DEF_ERROR_CODE(0, 0x0915) // internal
 #define TSDB_CODE_SYN_BUFFER_FULL               TAOS_DEF_ERROR_CODE(0, 0x0916)
 #define TSDB_CODE_SYN_WRITE_STALL               TAOS_DEF_ERROR_CODE(0, 0x0917)
-#define TSDB_CODE_SYN_NEGO_WIN_EXCEEDED         TAOS_DEF_ERROR_CODE(0, 0X0918)
+#define TSDB_CODE_SYN_NEGOTIATION_WIN_FULL      TAOS_DEF_ERROR_CODE(0, 0x0918)
 #define TSDB_CODE_SYN_INTERNAL_ERROR            TAOS_DEF_ERROR_CODE(0, 0x09FF)
 
 // tq
@@ -573,7 +573,7 @@ int32_t* taosGetErrno();
 // wal
 // #define TSDB_CODE_WAL_APP_ERROR              TAOS_DEF_ERROR_CODE(0, 0x1000) // 2.x
 #define TSDB_CODE_WAL_FILE_CORRUPTED            TAOS_DEF_ERROR_CODE(0, 0x1001)
-#define TSDB_CODE_WAL_SIZE_LIMIT                TAOS_DEF_ERROR_CODE(0, 0x1002)
+// #define TSDB_CODE_WAL_SIZE_LIMIT             TAOS_DEF_ERROR_CODE(0, 0x1002) // unused
 #define TSDB_CODE_WAL_INVALID_VER               TAOS_DEF_ERROR_CODE(0, 0x1003)
 // #define TSDB_CODE_WAL_OUT_OF_MEMORY          TAOS_DEF_ERROR_CODE(0, 0x1004) // 2.x
 #define TSDB_CODE_WAL_LOG_NOT_EXIST             TAOS_DEF_ERROR_CODE(0, 0x1005)
diff --git a/source/libs/sync/src/syncMain.c b/source/libs/sync/src/syncMain.c
index cb1919d16ea1db667d841b58302363b17c6c05a0..499df4a98b6f6bc8fac65a916e2163313e020e5e 100644
--- a/source/libs/sync/src/syncMain.c
+++ b/source/libs/sync/src/syncMain.c
@@ -463,8 +463,7 @@ bool syncSnapshotRecving(int64_t rid) {
 int32_t syncNodeLeaderTransfer(SSyncNode* pSyncNode) {
   if (pSyncNode->peersNum == 0) {
     sDebug("vgId:%d, only one replica, cannot leader transfer", pSyncNode->vgId);
-    terrno = TSDB_CODE_SYN_ONE_REPLICA;
-    return -1;
+    return 0;
   }
 
   int32_t ret = 0;
@@ -486,7 +485,6 @@ int32_t syncNodeLeaderTransfer(SSyncNode* pSyncNode) {
 int32_t syncNodeLeaderTransferTo(SSyncNode* pSyncNode, SNodeInfo newLeader) {
   if (pSyncNode->replicaNum == 1) {
     sDebug("vgId:%d, only one replica, cannot leader transfer", pSyncNode->vgId);
-    terrno = TSDB_CODE_SYN_ONE_REPLICA;
     return -1;
   }
 
diff --git a/source/libs/sync/src/syncPipeline.c b/source/libs/sync/src/syncPipeline.c
index 85c18220a6d9cb362bca2b45cad418b6db7502dd..8bb72de518cd7ae4f91d0a6db631f7bc34aeeffc 100644
--- a/source/libs/sync/src/syncPipeline.c
+++ b/source/libs/sync/src/syncPipeline.c
@@ -54,7 +54,7 @@ int32_t syncLogBufferAppend(SSyncLogBuffer* pBuf, SSyncNode* pNode, SSyncRaftEnt
   }
 
   if (pNode->restoreFinish && index - pBuf->commitIndex >= TSDB_SYNC_NEGOTIATION_WIN) {
-    terrno = TSDB_CODE_SYN_NEGO_WIN_EXCEEDED;
+    terrno = TSDB_CODE_SYN_NEGOTIATION_WIN_FULL;
     sError("vgId:%d, failed to append since %s, index:%" PRId64 ", commit-index:%" PRId64, pNode->vgId, terrstr(),
            index, pBuf->commitIndex);
     goto _err;
diff --git a/source/util/src/terror.c b/source/util/src/terror.c
index 1d9d45f26f342277101ec1bd5eac82c0306e55a7..6fc16ad4a98b517f4b5c37c48128e1b7d46248a0 100644
--- a/source/util/src/terror.c
+++ b/source/util/src/terror.c
@@ -414,20 +414,14 @@ TAOS_DEFINE_ERROR(TSDB_CODE_GRANT_TABLE_LIMITED,          "Table creation limite
 
 // sync
 TAOS_DEFINE_ERROR(TSDB_CODE_SYN_TIMEOUT,                  "Sync timeout")
-TAOS_DEFINE_ERROR(TSDB_CODE_SYN_IS_LEADER,                "Sync is leader")
 TAOS_DEFINE_ERROR(TSDB_CODE_SYN_NOT_LEADER,               "Sync leader is unreachable")
-TAOS_DEFINE_ERROR(TSDB_CODE_SYN_ONE_REPLICA,              "Sync one replica")
-TAOS_DEFINE_ERROR(TSDB_CODE_SYN_NOT_IN_NEW_CONFIG,        "Sync not in new config")
 TAOS_DEFINE_ERROR(TSDB_CODE_SYN_NEW_CONFIG_ERROR,         "Sync new config error")
-TAOS_DEFINE_ERROR(TSDB_CODE_SYN_RECONFIG_NOT_READY,       "Sync not ready for reconfig")
-TAOS_DEFINE_ERROR(TSDB_CODE_SYN_PROPOSE_NOT_READY,        "Sync not ready for propose")
-TAOS_DEFINE_ERROR(TSDB_CODE_SYN_STANDBY_NOT_READY,        "Sync not ready for standby")
-TAOS_DEFINE_ERROR(TSDB_CODE_SYN_BATCH_ERROR,              "Sync batch error")
+TAOS_DEFINE_ERROR(TSDB_CODE_SYN_PROPOSE_NOT_READY,        "Sync not ready to propose")
 TAOS_DEFINE_ERROR(TSDB_CODE_SYN_RESTORING,                "Sync leader is restoring")
 TAOS_DEFINE_ERROR(TSDB_CODE_SYN_INVALID_SNAPSHOT_MSG,     "Sync invalid snapshot msg")
 TAOS_DEFINE_ERROR(TSDB_CODE_SYN_BUFFER_FULL,              "Sync buffer is full")
 TAOS_DEFINE_ERROR(TSDB_CODE_SYN_WRITE_STALL,              "Sync write stall")
-TAOS_DEFINE_ERROR(TSDB_CODE_SYN_NEGO_WIN_EXCEEDED,        "Sync negotiation win exceeded")
+TAOS_DEFINE_ERROR(TSDB_CODE_SYN_NEGOTIATION_WIN_FULL,     "Sync negotiation win is full")
 TAOS_DEFINE_ERROR(TSDB_CODE_SYN_INTERNAL_ERROR,           "Sync internal error")
 
 //tq
@@ -445,8 +439,7 @@ TAOS_DEFINE_ERROR(TSDB_CODE_TQ_NO_COMMITTED_OFFSET,       "TQ no committed offse
 
 // wal
 TAOS_DEFINE_ERROR(TSDB_CODE_WAL_FILE_CORRUPTED,           "WAL file is corrupted")
-TAOS_DEFINE_ERROR(TSDB_CODE_WAL_SIZE_LIMIT,               "WAL size exceeds limit")
-TAOS_DEFINE_ERROR(TSDB_CODE_WAL_INVALID_VER,              "WAL use invalid version")
+TAOS_DEFINE_ERROR(TSDB_CODE_WAL_INVALID_VER,              "WAL invalid version")
 TAOS_DEFINE_ERROR(TSDB_CODE_WAL_LOG_NOT_EXIST,            "WAL log not exist")
 TAOS_DEFINE_ERROR(TSDB_CODE_WAL_CHKSUM_MISMATCH,          "WAL checksum mismatch")
 TAOS_DEFINE_ERROR(TSDB_CODE_WAL_LOG_INCOMPLETE,           "WAL log incomplete")