diff --git a/src/inc/taosdef.h b/src/inc/taosdef.h
index 71c2b15ab985e4e25569adc1eabfe31c94aced2d..61e82720b123a1249c6bfeefa99366b99a58a8a7 100644
--- a/src/inc/taosdef.h
+++ b/src/inc/taosdef.h
@@ -218,7 +218,7 @@ void tsDataSwap(void *pLeft, void *pRight, int32_t type, int32_t size);
 #define TSDB_LOCALE_LEN           64
 #define TSDB_TIMEZONE_LEN         64
 
-#define TSDB_FQDN_LEN             256
+#define TSDB_FQDN_LEN             72
 #define TSDB_IPv4ADDR_LEN      	  16
 #define TSDB_FILENAME_LEN         128
 #define TSDB_METER_VNODE_BITS     20