diff --git a/lib/isc/unix/socket.c b/lib/isc/unix/socket.c
index 62c8289932..b599932d4f 100644
--- a/lib/isc/unix/socket.c
+++ b/lib/isc/unix/socket.c
@@ -2018,7 +2018,6 @@ set_sndbuf(void) {
 	socklen_t len;
 
 	fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
-#if defined(ISC_PLATFORM_HAVEIPV6)
 	if (fd == -1) {
 		switch (errno) {
 		case EPROTONOSUPPORT:
@@ -2033,7 +2032,6 @@ set_sndbuf(void) {
 			break;
 		}
 	}
-#endif /* if defined(ISC_PLATFORM_HAVEIPV6) */
 	if (fd == -1) {
 		return;
 	}
@@ -2348,8 +2346,6 @@ again:
 #endif /* IPV6_RECVPKTINFO */
 #endif /* defined(USE_CMSG) */
 
-		set_ip_dontfrag(sock);
-
 #if defined(SET_RCVBUF)
 		optlen = sizeof(size);
 		if (getsockopt(sock->fd, SOL_SOCKET, SO_RCVBUF, (void *)&size,
@@ -2416,6 +2412,8 @@ again:
 #endif /* ifdef IP_RECVTOS */
 #endif /* defined(USE_CMSG) || defined(SET_RCVBUF) || defined(SET_SNDBUF) */
 
+	set_ip_dontfrag(sock);
+
 setup_done:
 	inc_stats(manager->stats, sock->statsindex[STATID_OPEN]);
 	if (sock->active == 0) {