diff --git a/src/dns_client.c b/src/dns_client.c
index 87b258c..ffacc8b 100644
--- a/src/dns_client.c
+++ b/src/dns_client.c
@@ -1843,7 +1843,8 @@ static int _dns_client_create_socket_udp(struct dns_server_info *server_info)
 	server_info->status = DNS_SERVER_STATUS_CONNECTIONLESS;
 
 	if (connect(fd, &server_info->addr, server_info->ai_addrlen) != 0) {
-		if (errno == ENETUNREACH || errno == EHOSTUNREACH || errno == ECONNREFUSED) {
+		if (errno == ENETUNREACH || errno == EHOSTUNREACH || errno == ECONNREFUSED || errno == EPERM ||
+			errno == EACCES) {
 			tlog(TLOG_INFO, "connect %s failed, %s", server_info->ip, strerror(errno));
 			goto errout;
 		}
@@ -3567,7 +3568,8 @@ static int _dns_client_send_packet(struct dns_query_struct *query, void *packet,
 		time(&now);
 		if (now - lastlog > 120) {
 			lastlog = now;
-			tlog(TLOG_WARN, "Send query %s to upstream server failed, total server number %d", query->domain, total_server);
+			tlog(TLOG_WARN, "Send query %s to upstream server failed, total server number %d", query->domain,
+				 total_server);
 		}
 		return -1;
 	}
diff --git a/src/dns_conf.c b/src/dns_conf.c
index b6c331a..b791145 100644
--- a/src/dns_conf.c
+++ b/src/dns_conf.c
@@ -83,7 +83,7 @@ static struct config_enum_list dns_conf_response_mode_enum[] = {
 enum response_mode_type dns_conf_response_mode;
 
 /* cache */
-int dns_conf_cachesize = -1;
+ssize_t dns_conf_cachesize = -1;
 int dns_conf_prefetch = 0;
 int dns_conf_serve_expired = 1;
 int dns_conf_serve_expired_ttl = 24 * 3600 * 3; /* 3 days */
@@ -3250,7 +3250,7 @@ static struct config_item _config_item[] = {
 	CONF_CUSTOM("nftset-no-speed", _config_nftset_no_speed, NULL),
 	CONF_CUSTOM("speed-check-mode", _config_speed_check_mode, NULL),
 	CONF_INT("tcp-idle-time", &dns_conf_tcp_idle_time, 0, 3600),
-	CONF_INT("cache-size", &dns_conf_cachesize, 0, CONF_INT_MAX),
+	CONF_SSIZE("cache-size", &dns_conf_cachesize, 0, CONF_INT_MAX),
 	CONF_CUSTOM("cache-file", _config_option_parser_filepath, (char *)&dns_conf_cache_file),
 	CONF_YESNO("cache-persist", &dns_conf_cache_persist),
 	CONF_YESNO("prefetch-domain", &dns_conf_prefetch),
diff --git a/src/dns_conf.h b/src/dns_conf.h
index eb8b69c..a7c1a48 100644
--- a/src/dns_conf.h
+++ b/src/dns_conf.h
@@ -434,7 +434,7 @@ extern char dns_conf_bind_ca_key_pass[DNS_MAX_PATH];
 extern char dns_conf_need_cert;
 
 extern int dns_conf_tcp_idle_time;
-extern int dns_conf_cachesize;
+extern ssize_t dns_conf_cachesize;
 extern int dns_conf_prefetch;
 extern int dns_conf_serve_expired;
 extern int dns_conf_serve_expired_ttl;
diff --git a/src/include/conf.h b/src/include/conf.h
index 538c21c..e201662 100644
--- a/src/include/conf.h
+++ b/src/include/conf.h
@@ -71,6 +71,12 @@ struct config_item_size {
 	size_t max;
 };
 
+struct config_item_ssize {
+	ssize_t *data;
+	ssize_t min;
+	ssize_t max;
+};
+
 struct config_enum_list {
 	char *name;
 	int id;
@@ -116,6 +122,13 @@ struct config_enum {
 			.data = value, .min = min_value, .max = max_value                                                          \
 		}                                                                                                              \
 	}
+#define CONF_SSIZE(key, value, min_value, max_value)                                                                    \
+	{                                                                                                                  \
+		key, conf_ssize, &(struct config_item_ssize)                                                                     \
+		{                                                                                                              \
+			.data = value, .min = min_value, .max = max_value                                                          \
+		}                                                                                                              \
+	}
 
 #define CONF_ENUM(key, value, enum)                                                                                    \
 	{                                                                                                                  \
@@ -153,6 +166,8 @@ extern int conf_yesno(const char *item, void *data, int argc, char *argv[]);
 
 extern int conf_size(const char *item, void *data, int argc, char *argv[]);
 
+extern int conf_ssize(const char *item, void *data, int argc, char *argv[]);
+
 extern int conf_enum(const char *item, void *data, int argc, char *argv[]);
 
 /*
diff --git a/src/lib/conf.c b/src/lib/conf.c
index b64303a..3980143 100644
--- a/src/lib/conf.c
+++ b/src/lib/conf.c
@@ -189,6 +189,39 @@ int conf_size(const char *item, void *data, int argc, char *argv[])
 	return 0;
 }
 
+int conf_ssize(const char *item, void *data, int argc, char *argv[])
+{
+	int base = 1;
+	ssize_t size = 0;
+	int num = 0;
+	struct config_item_ssize *item_size = data;
+	char *value = argv[1];
+
+	if (strstr(value, "k") || strstr(value, "K")) {
+		base = 1024;
+	} else if (strstr(value, "m") || strstr(value, "M")) {
+		base = 1024 * 1024;
+	} else if (strstr(value, "g") || strstr(value, "G")) {
+		base = 1024 * 1024 * 1024;
+	}
+
+	num = atoi(value);
+	if (num < 0) {
+		return -1;
+	}
+
+	size = num * base;
+	if (size > item_size->max) {
+		size = item_size->max;
+	} else if (size < item_size->min) {
+		size = item_size->min;
+	}
+
+	*(item_size->data) = size;
+
+	return 0;
+}
+
 int conf_enum(const char *item, void *data, int argc, char *argv[])
 {
 	struct config_enum *item_enum = data;