diff --git a/src/inc/dnode.h b/src/inc/dnode.h
index fa5e3a3b3d..db39906c68 100644
--- a/src/inc/dnode.h
+++ b/src/inc/dnode.h
@@ -42,7 +42,7 @@ void *dnodeAllocateWqueue(void *pVnode);
 void  dnodeFreeWqueue(void *queue);
 void *dnodeAllocateRqueue(void *pVnode);
 void  dnodeFreeRqueue(void *rqueue);
-void  dnodeSendWriteResponse(void *pVnode, void *param, int32_t code);
+void  dnodeSendRpcWriteRsp(void *pVnode, void *param, int32_t code);
 
 #ifdef __cplusplus
 }
diff --git a/src/inc/tsync.h b/src/inc/tsync.h
index 555e0503da..ea20ceec79 100644
--- a/src/inc/tsync.h
+++ b/src/inc/tsync.h
@@ -66,11 +66,11 @@ typedef struct {
   // if name is null, get the file from index or after, used by master
   // if name is provided, get the named file at the specified index, used by unsynced node
   // it returns the file magic number and size, if file not there, magic shall be 0.
-  uint32_t   (*getFileInfo)(char *name, int *index, int *size); 
+  uint32_t   (*getFileInfo)(void *ahandle, char *name, uint32_t *index, int32_t *size); 
 
   // get the wal file from index or after
   // return value, -1: error, 1:more wal files, 0:last WAL. if name[0]==0, no WAL file
-  int        (*getWalInfo)(char *name, int *index); 
+  int        (*getWalInfo)(void *ahandle, char *name, uint32_t *index); 
  
   // when a forward pkt is received, call this to handle data 
   int        (*writeToCache)(void *ahandle, void *pHead, int type);
@@ -94,11 +94,13 @@ int     syncGetNodesRole(tsync_h shandle, SNodesRole *);
 
 extern  char *syncRole[];
 
+//global configurable parameters
 extern  int   tsMaxSyncNum;
 extern  int   tsSyncTcpThreads;
 extern  int   tsMaxWatchFiles;
 extern  short tsSyncPort;
 extern  int   tsMaxFwdInfo; 
+extern  int   sDebugFlag;
 
 #ifdef __cplusplus
 }
diff --git a/src/inc/twal.h b/src/inc/twal.h
index 3648f5ae29..53d4f835b0 100644
--- a/src/inc/twal.h
+++ b/src/inc/twal.h
@@ -40,12 +40,12 @@ typedef struct {
 
 typedef void* twal_h;  // WAL HANDLE
 
-twal_h  walOpen(char *path, int max, int level);
+twal_h  walOpen(char *path, SWalCfg *pCfg);
 void    walClose(twal_h);
 int     walRenew(twal_h);
 int     walWrite(twal_h, SWalHead *);
 void    walFsync(twal_h);
-int     walRestore(twal_h, void *pVnode, int (*writeFp)(void *ahandle, SWalHead *pHead, int type));
+int     walRestore(twal_h, void *pVnode, int (*writeFp)(void *ahandle, void *pHead, int type));
 int     walGetWalFile(twal_h, char *name, uint32_t *index);
 
 extern int wDebugFlag;
diff --git a/src/vnode/main/inc/vnodeInt.h b/src/vnode/main/inc/vnodeInt.h
index 4d078869c4..75d3117eac 100644
--- a/src/vnode/main/inc/vnodeInt.h
+++ b/src/vnode/main/inc/vnodeInt.h
@@ -35,7 +35,7 @@ typedef struct {
   int32_t      vgId;      // global vnode group ID
   int32_t      refCount;  // reference count
   EVnStatus    status; 
-  int          role;   
+  int8_t       role;   
   int64_t      version;
   void        *wqueue;
   void        *rqueue;
@@ -49,7 +49,7 @@ typedef struct {
   SWalCfg     walCfg;
 } SVnodeObj;
 
-int  vnodeWriteToQueue(void *param, SWalHead *pHead, int type);
+int  vnodeWriteToQueue(void *param, void *pHead, int type);
 void vnodeInitWriteFp(void);
 void vnodeInitReadFp(void);
 
diff --git a/src/vnode/main/src/vnodeMain.c b/src/vnode/main/src/vnodeMain.c
index 1211828a47..a3c60c4387 100644
--- a/src/vnode/main/src/vnodeMain.c
+++ b/src/vnode/main/src/vnodeMain.c
@@ -29,13 +29,18 @@
 #include "vnode.h"
 #include "vnodeInt.h"
 
-static void   *tsDnodeVnodesHash;
-static void    vnodeCleanUp(SVnodeObj *pVnode);
-static void    vnodeBuildVloadMsg(char *pNode, void * param);
-static int     vnodeWALCallback(void *arg);
-static int32_t vnodeSaveCfg(SMDCreateVnodeMsg *pVnodeCfg);
-static int32_t vnodeReadCfg(SVnodeObj *pVnode);
+static void    *tsDnodeVnodesHash;
+static void     vnodeCleanUp(SVnodeObj *pVnode);
+static void     vnodeBuildVloadMsg(char *pNode, void * param);
+static int      vnodeWalCallback(void *arg);
+static int32_t  vnodeSaveCfg(SMDCreateVnodeMsg *pVnodeCfg);
+static int32_t  vnodeReadCfg(SVnodeObj *pVnode);
+static int      vnodeWalCallback(void *arg);
+static uint32_t vnodeGetFileInfo(void *ahandle, char *name, uint32_t *index, int32_t *size);
+static int      vnodeGetWalInfo(void *ahandle, char *name, uint32_t *index);
+static void     vnodeNotifyRole(void *ahandle, int8_t role);
 
+// module global
 static int   tsOpennedVnodes;
 static pthread_once_t  vnodeModuleInit = PTHREAD_ONCE_INIT;
 
@@ -140,14 +145,27 @@ int32_t vnodeOpen(int32_t vnode, char *rootDir) {
   pVnode->rqueue = dnodeAllocateRqueue(pVnode);
 
   sprintf(temp, "%s/wal", rootDir);
-  pVnode->wal      = walOpen(temp, pVnode->walCfg.wals, pVnode->walCfg.commitLog);
-  pVnode->sync     = NULL;
+  pVnode->wal      = walOpen(temp, &pVnode->walCfg);
+
+  SSyncInfo syncInfo;
+  syncInfo.vgId = pVnode->vgId;
+  syncInfo.vgId = pVnode->version;
+  syncInfo.syncCfg = pVnode->syncCfg;
+  sprintf(syncInfo.path, "%s/tsdb/", rootDir);
+  syncInfo.ahandle = pVnode;
+  syncInfo.getWalInfo = vnodeGetWalInfo;
+  syncInfo.getFileInfo = vnodeGetFileInfo;
+  syncInfo.writeToCache = vnodeWriteToQueue;
+  syncInfo.confirmForward = dnodeSendRpcWriteRsp; 
+  syncInfo.notifyRole = vnodeNotifyRole;
+  // pVnode->sync     = syncStart(&syncInfo);;
+
   pVnode->events   = NULL;
   pVnode->cq       = NULL;
 
   STsdbAppH appH = {0};
   appH.appH = (void *)pVnode;
-  appH.walCallBack = vnodeWALCallback;
+  appH.walCallBack = vnodeWalCallback;
 
   sprintf(temp, "%s/tsdb", rootDir);
   void *pTsdb = tsdbOpenRepo(temp, &appH);
@@ -281,11 +299,27 @@ static void vnodeCleanUp(SVnodeObj *pVnode) {
 }
 
 // TODO: this is a simple implement
-static int vnodeWALCallback(void *arg) {
+static int vnodeWalCallback(void *arg) {
   SVnodeObj *pVnode = arg;
   return walRenew(pVnode->wal);
 }
 
+static uint32_t vnodeGetFileInfo(void *ahandle, char *name, uint32_t *index, int32_t *size) {
+  // SVnodeObj *pVnode = ahandle;
+  //tsdbGetFileInfo(pVnode->tsdb, name, index, size);
+  return 0;
+}
+
+static int vnodeGetWalInfo(void *ahandle, char *name, uint32_t *index) {
+  SVnodeObj *pVnode = ahandle;
+  return walGetWalFile(pVnode->wal, name, index);
+}
+
+static void vnodeNotifyRole(void *ahandle, int8_t role) {
+  SVnodeObj *pVnode = ahandle;
+  pVnode->role = role;
+}
+
 static int32_t vnodeSaveCfg(SMDCreateVnodeMsg *pVnodeCfg) {
   char cfgFile[TSDB_FILENAME_LEN * 2] = {0};
   sprintf(cfgFile, "%s/vnode%d/config", tsVnodeDir, pVnodeCfg->cfg.vgId);
diff --git a/src/vnode/main/src/vnodeWrite.c b/src/vnode/main/src/vnodeWrite.c
index c6699bd62c..fc73850f40 100644
--- a/src/vnode/main/src/vnodeWrite.c
+++ b/src/vnode/main/src/vnodeWrite.c
@@ -248,8 +248,9 @@ static int32_t vnodeProcessDropStableMsg(SVnodeObj *pVnode, void *pCont, SRspRet
   return code;
 }
 
-int vnodeWriteToQueue(void *param, SWalHead *pHead, int type) {
+int vnodeWriteToQueue(void *param, void *data, int type) {
   SVnodeObj *pVnode = param;
+  SWalHead *pHead = data;
 
   int size = sizeof(SWalHead) + pHead->len;
   SWalHead *pWal = (SWalHead *)taosAllocateQitem(size);
diff --git a/src/vnode/wal/src/walMain.c b/src/vnode/wal/src/walMain.c
index 99de5cceda..7c5602680f 100644
--- a/src/vnode/wal/src/walMain.c
+++ b/src/vnode/wal/src/walMain.c
@@ -49,18 +49,18 @@ int wDebugFlag = 135;
 
 static uint32_t walSignature = 0xFAFBFDFE;
 static int walHandleExistingFiles(char *path);
-static int walRestoreWalFile(char *name, void *pVnode, int (*writeFp)(void *, SWalHead *, int));
+static int walRestoreWalFile(char *name, void *pVnode, int (*writeFp)(void *, void *, int));
 static int walRemoveWalFiles(char *path);
 
-void *walOpen(char *path, int max, int level) {
+void *walOpen(char *path, SWalCfg *pCfg) {
   SWal *pWal = calloc(sizeof(SWal), 1);
   if (pWal == NULL) return NULL;
 
   pWal->fd = -1;
-  pWal->max = max;
+  pWal->max = pCfg->wals;
   pWal->id = 0;
   pWal->num = 0;
-  pWal->level = level;
+  pWal->level = pCfg->commitLog;
   strcpy(pWal->path, path);
   pthread_mutex_init(&pWal->mutex, NULL);
 
@@ -169,7 +169,7 @@ void walFsync(void *handle) {
     fsync(pWal->fd);
 }
 
-int walRestore(void *handle, void *pVnode, int (*writeFp)(void *, SWalHead *, int)) {
+int walRestore(void *handle, void *pVnode, int (*writeFp)(void *, void *, int)) {
   SWal    *pWal = (SWal *)handle;
   int      code = 0;
   struct   dirent *ent;
@@ -246,7 +246,7 @@ int walGetWalFile(void *handle, char *name, uint32_t *index) {
   return code;
 }  
 
-static int walRestoreWalFile(char *name, void *pVnode, int (*writeFp)(void *, SWalHead *, int)) {
+static int walRestoreWalFile(char *name, void *pVnode, int (*writeFp)(void *, void *, int)) {
   int code = 0;
 
   char *buffer = malloc(1024000);  // size for one record
diff --git a/src/vnode/wal/test/waltest.c b/src/vnode/wal/test/waltest.c
index 37d1d8e84c..8e10bc11e5 100644
--- a/src/vnode/wal/test/waltest.c
+++ b/src/vnode/wal/test/waltest.c
@@ -21,8 +21,10 @@
 int64_t  ver = 0;
 void    *pWal = NULL;
 
-int writeToQueue(void *pVnode, SWalHead *pHead, int type) {
+int writeToQueue(void *pVnode, void *data, int type) {
   // do nothing
+  SWalHead *pHead = data;
+
   if (pHead->version > ver)
     ver = pHead->version;
 
@@ -74,7 +76,11 @@ int main(int argc, char *argv[]) {
 
   taosInitLog("wal.log", 100000, 10);
 
-  pWal = walOpen(path, max, level);
+  SWalCfg walCfg;
+  walCfg.commitLog = level;
+  walCfg.wals = max;
+
+  pWal = walOpen(path, &walCfg);
   if (pWal == NULL) {
     printf("failed to open wal\n");
     exit(-1);