diff --git a/src/lib/io/master.c b/src/lib/io/master.c
index 04bff39628713..422fa87933844 100644
--- a/src/lib/io/master.c
+++ b/src/lib/io/master.c
@@ -1364,6 +1364,11 @@ static ssize_t mod_read(fr_listen_t *li, void **packet_ctx, fr_time_t *recv_time
 			return 0;
 		}
 
+		/*
+		 *	Set the new descriptor to be non-blocking.
+		 */
+		(void) fr_nonblock(accept_fd);
+
 #ifdef STATIC_ANALYZER
 		saremote.ss_family = AF_INET; /* static analyzer doesn't know that accept() initializes this */
 #endif