diff --git a/doc/configuration.txt b/doc/configuration.txt
index 3acf5c15e..89cededa0 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -2193,6 +2193,7 @@ dns-accept-family <family>[,...]
     - "ipv4": query and accept IPv4 addresses ("A" records)
     - "ipv6": query and accept IPv6 addresses ("AAAA" records)
     - "auto": use IPv4, and IPv6 if the system has a default gateway for it.
+              The result of the last check is cached for 30 seconds.
 
   When a single family is used, no request will be sent to resolvers for the
   other family, and any response for the othe family will be ignored. The
diff --git a/include/haproxy/defaults.h b/include/haproxy/defaults.h
index c18b2f079..7eba11ef6 100644
--- a/include/haproxy/defaults.h
+++ b/include/haproxy/defaults.h
@@ -349,6 +349,11 @@
 #define SRV_CHK_INTER_THRES 1000
 #endif
 
+/* INET6 connectivity caching interval (in ms) */
+#ifndef INET6_CONNECTIVITY_CACHE_TIME
+#define INET6_CONNECTIVITY_CACHE_TIME 30000
+#endif
+
 /* Specifies the string used to report the version and release date on the
  * statistics page. May be defined to the empty string ("") to permanently
  * disable the feature.
diff --git a/include/haproxy/sock_inet.h b/include/haproxy/sock_inet.h
index 1d4a8b7a0..ad756558d 100644
--- a/include/haproxy/sock_inet.h
+++ b/include/haproxy/sock_inet.h
@@ -31,6 +31,7 @@ extern int sock_inet6_v6only_default;
 extern int sock_inet_tcp_maxseg_default;
 extern int sock_inet6_tcp_maxseg_default;
 extern int sock_inet6_seems_reachable;
+extern uint last_inet6_check;
 
 #ifdef HA_HAVE_MPTCP
 extern int sock_inet_mptcp_maxseg_default;
@@ -54,5 +55,6 @@ int sock_inet_is_foreign(int fd, sa_family_t family);
 int sock_inet4_make_foreign(int fd);
 int sock_inet6_make_foreign(int fd);
 int sock_inet_bind_receiver(struct receiver *rx, char **errmsg);
+int is_inet6_reachable(void);
 
 #endif /* _HAPROXY_SOCK_INET_H */
diff --git a/src/resolvers.c b/src/resolvers.c
index f8378a18b..d52303381 100644
--- a/src/resolvers.c
+++ b/src/resolvers.c
@@ -225,7 +225,7 @@ static inline int resolv_active_families(void)
 {
 	if (resolv_accept_families & RSLV_AUTO_FAMILY) {
 		/* Let's adjust our default resolver families based on apparent IPv6 connectivity */
-		if (sock_inet6_seems_reachable)
+		if (is_inet6_reachable())
 			return RSLV_ACCEPT_IPV4 | RSLV_ACCEPT_IPV6;
 		else
 			return RSLV_ACCEPT_IPV4;
diff --git a/src/sock_inet.c b/src/sock_inet.c
index cf60c5a1c..abe99b360 100644
--- a/src/sock_inet.c
+++ b/src/sock_inet.c
@@ -81,6 +81,7 @@ int sock_inet6_tcp_maxseg_default = -1;
 
 /* indicate whether v6 looks reachable (this is only a hint) */
 int sock_inet6_seems_reachable = 0;
+uint last_inet6_check = TICK_ETERNITY;
 
 /* Default MPTCPv4/MPTCPv6 MSS settings. -1=unknown. */
 #ifdef HA_HAVE_MPTCP
@@ -472,6 +473,45 @@ int sock_inet_bind_receiver(struct receiver *rx, char **errmsg)
 	goto bind_return;
 }
 
+
+/* Detects IPv6 reachability: for this we perform a UDP connect to address
+ * 2001:: on port 53. No packet will be sent, it will just check the routing
+ * table towards this prefix for the majority of public addresses. In case of
+ * error we assume no IPv6 connectivity.
+ *
+ * Returns non-zero if inet6 looks reachable, otherwise zero. This considers
+ * the last result if it ages less than 30s, otherwise triggers a new test
+ * which updates <sock_inet6_seems_reachable> and <last_inet6_check>.
+ */
+int is_inet6_reachable(void)
+{
+	uint last_check = HA_ATOMIC_LOAD(&last_inet6_check);
+	struct sockaddr_in6 dest = { };
+	int ret = 0;
+	int fd;
+
+	if (tick_isset(last_check) &&
+	    !tick_is_expired(tick_add(last_check, INET6_CONNECTIVITY_CACHE_TIME), HA_ATOMIC_LOAD(&global_now_ms)))
+		return HA_ATOMIC_LOAD(&sock_inet6_seems_reachable);
+
+	/* update the test date to ensure nobody else does it in parallel */
+	HA_ATOMIC_STORE(&last_inet6_check, HA_ATOMIC_LOAD(&global_now_ms));
+
+	fd = socket(AF_INET6, SOCK_DGRAM, 0);
+	if (fd >= 0) {
+		dest.sin6_family = AF_INET6;
+		dest.sin6_addr.s6_addr[0] = 0x20;
+		dest.sin6_addr.s6_addr[1] = 0x01;
+		dest.sin6_port = htons(53);
+		if (connect(fd, (struct sockaddr*)&dest, sizeof(dest)) == 0)
+			ret = 1;
+		close(fd);
+	}
+
+	HA_ATOMIC_STORE(&sock_inet6_seems_reachable, ret);
+	return ret;
+}
+
 static void sock_inet_prepare()
 {
 	int fd, val;
@@ -529,24 +569,6 @@ static void sock_inet_prepare()
 		close(fd);
 	}
 #endif
-
-	/* detect IPv6 reachability: for this we perform a UDP connect to
-	 * address 2001:: on port 53. No packet will be sent, it will just
-	 * check the routing table towards this prefix for the majority of
-	 * public addresses. In case of error we assume no IPv6 connectivity.
-	 */
-	fd = socket(AF_INET6, SOCK_DGRAM, 0);
-	if (fd >= 0) {
-		struct sockaddr_in6 dest = { };
-
-		dest.sin6_family = AF_INET6;
-		dest.sin6_addr.s6_addr[0] = 0x20;
-		dest.sin6_addr.s6_addr[1] = 0x01;
-		dest.sin6_port = htons(53);
-		if (connect(fd, (struct sockaddr*)&dest, sizeof(dest)) == 0)
-			sock_inet6_seems_reachable = 1;
-		close(fd);
-	}
 }
 
 INITCALL0(STG_PREPARE, sock_inet_prepare);