diff --git a/include/haproxy/http.h b/include/haproxy/http.h
index 299264051..e28f3cc90 100644
--- a/include/haproxy/http.h
+++ b/include/haproxy/http.h
@@ -27,15 +27,20 @@
 #include <import/ist.h>
 #include <haproxy/api.h>
 #include <haproxy/http-t.h>
+#include <haproxy/intops.h>
 
 extern const int http_err_codes[HTTP_ERR_SIZE];
 extern const char *http_err_msgs[HTTP_ERR_SIZE];
 extern const struct ist http_known_methods[HTTP_METH_OTHER];
 extern const uint8_t http_char_classes[256];
+extern long http_err_status_codes[512 / sizeof(long)];
+extern long http_fail_status_codes[512 / sizeof(long)];
 
 enum http_meth_t find_http_meth(const char *str, const int len);
 int http_get_status_idx(unsigned int status);
 const char *http_get_reason(unsigned int status);
+void http_status_add_range(long *array, uint low, uint high);
+void http_status_del_range(long *array, uint low, uint high);
 struct ist http_get_host_port(const struct ist host);
 int http_is_default_port(const struct ist schm, const struct ist port);
 int http_validate_scheme(const struct ist schm);
@@ -212,6 +217,18 @@ static inline int http_path_has_forbidden_char(const struct ist ist, const char
 	return 0;
 }
 
+/* Checks status code array <array> for the presence of status code <status>.
+ * Returns non-zero if the code is present, zero otherwise. Any status code is
+ * permitted.
+ */
+static inline int http_status_matches(const long *array, uint status)
+{
+	if (status < 100 || status > 599)
+		return 0;
+
+	return ha_bit_test(status - 100, array);
+}
+
 #endif /* _HAPROXY_HTTP_H */
 
 /*
diff --git a/src/http.c b/src/http.c
index 072762d85..82da7bb13 100644
--- a/src/http.c
+++ b/src/http.c
@@ -344,6 +344,14 @@ const struct ist http_known_methods[HTTP_METH_OTHER] = {
 	[HTTP_METH_CONNECT] = IST("CONNECT"),
 };
 
+/* 500 bits to indicate for each status code from 100 to 599 if it participates
+ * to the error or failure class. The last 12 bits are not assigned for now.
+ * Not initialized, has to be done at boot. This is manipulated using
+ * http_status_{add,del}_range().
+ */
+long http_err_status_codes[512 / sizeof(long)] = { };
+long http_fail_status_codes[512 / sizeof(long)] = { };
+
 /*
  * returns a known method among HTTP_METH_* or HTTP_METH_OTHER for all unknown
  * ones.
@@ -477,6 +485,40 @@ const char *http_get_reason(unsigned int status)
 	}
 }
 
+/* add status codes from low to high included to status codes array <array>
+ * which must be compatible with http_err_codes and http_fail_codes (i.e. 512
+ * bits each). This is not thread save and is meant for being called during
+ * boot only. Only status codes 100-599 are permitted.
+ */
+void http_status_add_range(long *array, uint low, uint high)
+{
+	low -= 100;
+	high -= 100;
+
+	BUG_ON(low > 499);
+	BUG_ON(high > 499);
+
+	while (low <= high)
+		ha_bit_set(low++, array);
+}
+
+/* remove status codes from low to high included to status codes array <array>
+ * which must be compatible with http_err_codes and http_fail_codes (i.e. 512
+ * bits each). This is not thread save and is meant for being called during
+ * boot only. Only status codes 100-599 are permitted.
+ */
+void http_status_del_range(long *array, uint low, uint high)
+{
+	low -= 100;
+	high -= 100;
+
+	BUG_ON(low > 499);
+	BUG_ON(high > 499);
+
+	while (low <= high)
+		ha_bit_clr(low++, array);
+}
+
 /* Returns the ist string corresponding to port part (without ':') in the host
  * <host>, IST_NULL if no ':' is found or an empty IST if there is no digit. In
  * the last case, the result is the original ist trimmed to 0. So be sure to test
@@ -1430,3 +1472,14 @@ struct ist http_trim_trailing_spht(struct ist value)
 
 	return ret;
 }
+
+/* initialize the required structures and arrays */
+static void _http_init()
+{
+	/* preset the default status codes that count as errors and failures */
+	http_status_add_range(http_err_status_codes,  400, 499);
+	http_status_add_range(http_fail_status_codes, 500, 599);
+	http_status_del_range(http_fail_status_codes, 501, 501);
+	http_status_del_range(http_fail_status_codes, 505, 505);
+}
+INITCALL0(STG_INIT, _http_init);