diff --git a/lib/dns/db.c b/lib/dns/db.c
index a0c4772205..04eb611922 100644
--- a/lib/dns/db.c
+++ b/lib/dns/db.c
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: db.c,v 1.52 2000/08/10 18:38:10 gson Exp $ */
+/* $Id: db.c,v 1.53 2000/08/18 18:25:25 bwelling Exp $ */
 
 /***
  *** Imports
@@ -192,6 +192,18 @@ dns_db_issecure(dns_db_t *db) {
 	return ((db->methods->issecure)(db));
 }
 
+isc_boolean_t
+dns_db_ispersistent(dns_db_t *db) {
+
+	/*
+	 * Is 'db' persistent?
+	 */
+
+	REQUIRE(DNS_DB_VALID(db));
+
+	return ((db->methods->ispersistent)(db));
+}
+
 dns_name_t *
 dns_db_origin(dns_db_t *db) {
 	/*
diff --git a/lib/dns/include/dns/db.h b/lib/dns/include/dns/db.h
index bc26ca2c42..9fc8fd8c6f 100644
--- a/lib/dns/include/dns/db.h
+++ b/lib/dns/include/dns/db.h
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: db.h,v 1.54 2000/08/03 19:46:36 bwelling Exp $ */
+/* $Id: db.h,v 1.55 2000/08/18 18:25:28 bwelling Exp $ */
 
 #ifndef DNS_DB_H
 #define DNS_DB_H 1
@@ -141,6 +141,7 @@ typedef struct dns_dbmethods {
 					  dns_rdatatype_t covers);
 	isc_boolean_t	(*issecure)(dns_db_t *db);
 	unsigned int	(*nodecount)(dns_db_t *db);
+	isc_boolean_t	(*ispersistent)(dns_db_t *db);
 } dns_dbmethods_t;
 
 #define DNS_DB_MAGIC		0x444E5344U		/* DNSD. */
@@ -1143,6 +1144,21 @@ dns_db_nodecount(dns_db_t *db);
  * 	The number of nodes in the database
  */
 
+unsigned int
+dns_db_ispersistent(dns_db_t *db);
+/*
+ * Is 'db' persistent?  A persistent database does not need to be loaded
+ * from disk or written to disk.
+ *
+ * Requires:
+ *
+ *	'db' is a valid database.
+ *
+ * Returns:
+ *	ISC_TRUE	'db' is persistent.
+ *	ISC_FALSE	'db' is not persistent.
+ */
+
 ISC_LANG_ENDDECLS
 
 #endif /* DNS_DB_H */
diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
index b8387a2bda..982f38d253 100644
--- a/lib/dns/rbtdb.c
+++ b/lib/dns/rbtdb.c
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: rbtdb.c,v 1.119 2000/08/14 02:49:32 gson Exp $ */
+/* $Id: rbtdb.c,v 1.120 2000/08/18 18:25:26 bwelling Exp $ */
 
 /*
  * Principal Author: Bob Halley
@@ -3795,6 +3795,12 @@ nodecount(dns_db_t *db) {
 	return (count);
 }
 
+static isc_boolean_t
+ispersistent(dns_db_t *db) {
+	UNUSED(db);
+	return (ISC_FALSE);
+}
+
 static dns_dbmethods_t zone_methods = {
 	attach,
 	detach,
@@ -3819,7 +3825,8 @@ static dns_dbmethods_t zone_methods = {
 	subtractrdataset,
 	deleterdataset,
 	issecure,
-	nodecount
+	nodecount,
+	ispersistent
 };
 
 static dns_dbmethods_t cache_methods = {
@@ -3846,7 +3853,8 @@ static dns_dbmethods_t cache_methods = {
 	subtractrdataset,
 	deleterdataset,
 	issecure,
-	nodecount
+	nodecount,
+	ispersistent
 };
 
 isc_result_t