diff --git a/tests/test_cache.c b/tests/test_cache.c
index 4aa0a5bd74dfe5d9eca16e3fb86d4f2119e7c1f2..ad49ce4be4fdc0d151012d06c9e378f0720a73fb 100644
--- a/tests/test_cache.c
+++ b/tests/test_cache.c
@@ -20,11 +20,19 @@
 #include "tests/test.h"
 #include "lib/cache.h"
 
+#include <stdlib.h>
+#include <time.h>
 
 mm_ctx_t global_mm;
 namedb_txn_t global_txn;
 knot_rrset_t global_rr;
 const char *global_env;
+struct kr_cache_entry global_fake_ce;
+
+#define NAMEDB_INTS 256
+#define NAMEDB_DATA_SIZE (NAMEDB_INTS * sizeof(int))
+uint8_t namedb_data[NAMEDB_DATA_SIZE];
+namedb_val_t global_namedb_data = {namedb_data, NAMEDB_DATA_SIZE};
 
 #define CACHE_SIZE 10 * 4096
 #define CACHE_TTL 10
@@ -48,14 +56,40 @@ static void test_abort(namedb_txn_t *txn)
 	return;
 }
 
-/* Fake api to simulate failures */
+/* Stub for find */
+static int test_find(namedb_txn_t *txn, namedb_val_t *key, namedb_val_t *val, unsigned flags)
+{
+    val->data = &global_fake_ce;
+    return KNOT_EOK;
+}
+
+/* Stub for insert */
+static int test_ins(namedb_txn_t *txn, namedb_val_t *key, namedb_val_t *val, unsigned flags)
+{
+    int err = KNOT_EINVAL, i, res_cmp;
+    struct kr_cache_entry *header = val->data;
+    if (val->len == sizeof (*header) + NAMEDB_DATA_SIZE)
+    {
+	header = val->data;
+	res_cmp  = memcmp(header->data,namedb_data,NAMEDB_DATA_SIZE);
+	if (header->timestamp == global_fake_ce.timestamp &&
+		header->ttl == global_fake_ce.ttl &&
+		    header->ttl == global_fake_ce.ttl &&
+			res_cmp == 0)
+	err = KNOT_EOK;
+    }
+    return err;
+}
+
+
+/* Fake api */
 static const namedb_api_t *namedb_lmdb_api_fake(void)
 {
 	static const namedb_api_t api_fake = {
 		"lmdb_api_fake",
 		test_init_failure, NULL,
 		NULL, test_commit_failure, test_abort,
-		NULL, NULL, NULL, NULL, NULL,
+		NULL, NULL, test_find, test_ins, NULL,
 		NULL, NULL, NULL, NULL, NULL, NULL
 	};
 
@@ -67,16 +101,27 @@ static const namedb_api_t *namedb_lmdb_api_fake(void)
 static void test_invalid(void **state)
 {
 	const namedb_api_t *(*kr_cache_storage_saved)(void);
-	void *ret_open;
-	int ret_commit;
+	void *ret_open, *ret_cache_peek;
+	int ret_commit, timestamp = CACHE_TIME;
 
 	assert_int_not_equal(kr_cache_txn_begin(NULL, &global_txn, 0), 0);
 	assert_int_not_equal(kr_cache_txn_begin(&global_env, NULL, 0), 0);
 	assert_int_not_equal(kr_cache_txn_commit(NULL), 0);
+	assert_null(kr_cache_peek(NULL, KR_CACHE_USER, "", KNOT_RRTYPE_TSIG, &timestamp));
+	assert_null(kr_cache_peek(&global_txn, 0, "", KNOT_RRTYPE_TSIG, &timestamp));
+	assert_null(kr_cache_peek(&global_txn, KR_CACHE_USER, NULL, KNOT_RRTYPE_TSIG, &timestamp));
 	assert_int_not_equal(kr_cache_peek_rr(NULL, NULL, NULL), 0);
 	assert_int_not_equal(kr_cache_peek_rr(&global_txn, NULL, NULL), 0);
 	assert_int_not_equal(kr_cache_insert_rr(&global_txn, NULL, 0), 0);
 	assert_int_not_equal(kr_cache_insert_rr(NULL, NULL, 0), 0);
+	assert_int_not_equal(kr_cache_insert(NULL, KR_CACHE_USER, "",
+		KNOT_RRTYPE_TSIG, &global_fake_ce, global_namedb_data), 0);
+	assert_int_not_equal(kr_cache_insert(&global_txn, 0, "",
+		KNOT_RRTYPE_TSIG, &global_fake_ce, global_namedb_data), 0);
+	assert_int_not_equal(kr_cache_insert(&global_txn, KR_CACHE_USER, NULL,
+		KNOT_RRTYPE_TSIG, &global_fake_ce, global_namedb_data), 0);
+	assert_int_not_equal(kr_cache_insert(&global_txn, KR_CACHE_USER, "",
+		KNOT_RRTYPE_TSIG, NULL, global_namedb_data), 0);
 	assert_int_not_equal(kr_cache_remove(&global_txn, 0, NULL, 0), 0);
 	assert_int_not_equal(kr_cache_remove(&global_txn, KR_CACHE_RR, NULL, 0), 0);
 	assert_int_not_equal(kr_cache_remove(NULL, 0, NULL, 0), 0);
@@ -84,14 +129,17 @@ static void test_invalid(void **state)
 
 	/* save original api */
 	kr_cache_storage_saved = kr_cache_storage;
-	/* fake to simulate failures */
+	/* fake to simulate failures or constant success */
 	kr_cache_storage_set(namedb_lmdb_api_fake);
 
+	/* call kr_cache_peek() with no time constraint */
+	ret_cache_peek = kr_cache_peek(&global_txn, KR_CACHE_USER, "", KNOT_RRTYPE_TSIG, 0);
 	ret_open = kr_cache_open(NULL, NULL);
 	ret_commit = kr_cache_txn_commit(&global_txn);
 
 	/* restore */
 	kr_cache_storage_set(kr_cache_storage_saved);
+	assert_int_equal(ret_cache_peek, &global_fake_ce);
 	assert_null(ret_open);
 	assert_int_not_equal(ret_commit, KNOT_EOK);
 }
@@ -134,6 +182,8 @@ static namedb_txn_t *test_txn_rdonly(void **state)
 /* Test cache write */
 static void test_insert(void **state)
 {
+	const namedb_api_t *(*kr_cache_storage_saved)(void);
+	int i, ret_cache_insert;
 	test_random_rr(&global_rr, CACHE_TTL);
 
 	namedb_txn_t *txn = test_txn_write(state);
@@ -145,6 +195,24 @@ static void test_insert(void **state)
 	}
 
 	assert_int_equal(ret, KNOT_EOK);
+
+	memset(&global_fake_ce,0xAA,sizeof(global_fake_ce));
+	srand(time(NULL));
+	for (i = 0; i < NAMEDB_DATA_SIZE; i += 4)
+	{
+	    int r = rand();
+	    namedb_data[i] = r;
+	    namedb_data[i + 1] = r >> 8;
+	    namedb_data[i + 2] = r >> 16;
+	    namedb_data[i + 3] = r >> 24;
+	}
+
+	kr_cache_storage_saved = kr_cache_storage;
+	kr_cache_storage_set(namedb_lmdb_api_fake);
+	ret_cache_insert = kr_cache_insert(&global_txn, KR_CACHE_USER, "",
+		KNOT_RRTYPE_TSIG, &global_fake_ce, global_namedb_data);
+	kr_cache_storage_set(kr_cache_storage_saved);
+	assert_int_equal(ret_cache_insert, KNOT_EOK);
 }
 
 /* Test cache read */