diff --git a/src/basic/errno-util.h b/src/basic/errno-util.h
index 0ca650f48f6..383615c288c 100644
--- a/src/basic/errno-util.h
+++ b/src/basic/errno-util.h
@@ -50,7 +50,10 @@ static inline int errno_or_else(int fallback) {
 /* Hint #1: ENETUNREACH happens if we try to connect to "non-existing" special IP addresses, such as ::5.
  *
  * Hint #2: The kernel sends e.g., EHOSTUNREACH or ENONET to userspace in some ICMP error cases.  See the
- *          icmp_err_convert[] in net/ipv4/icmp.c in the kernel sources */
+ *          icmp_err_convert[] in net/ipv4/icmp.c in the kernel sources.
+ *
+ * Hint #3: When asynchronous connect() on TCP fails because the host never acknowledges a single packet,
+ *          kernel tells us that with ETIMEDOUT, see tcp(7). */
 static inline bool ERRNO_IS_DISCONNECT(int r) {
         return IN_SET(abs(r),
                       ECONNABORTED,
@@ -66,7 +69,8 @@ static inline bool ERRNO_IS_DISCONNECT(int r) {
                       ENOTCONN,
                       EPIPE,
                       EPROTO,
-                      ESHUTDOWN);
+                      ESHUTDOWN,
+                      ETIMEDOUT);
 }
 
 /* Transient errors we might get on accept() that we should ignore. As per error handling comment in