daemon/udp_queue: drop the error logging

We should do this for all transports and probably just in verbose mode.
We were printing lots of these on Turris OS (for one user at least):
https://forum.turris.cz/t/5-1-8-kresd-throwing-many-errors-in-var-log-messages/14775

EACCESS in particular apparently may happen (on Linux) when the network
is "unavailable", EPERM because of firewall/netfilter:
https://stackoverflow.com/a/23869102

diff --git a/NEWS b/NEWS
index bb584f9a0ee18d1dc60ad6e7c7984726bc4e72f5..d8431c031719c6fc28c9f2bd15eea044aa5d86cc 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -8,6 +8,7 @@ Improvements
 - daf module: add daf.clear() (!1114)
 - dnstap module: more features and don't log internal requests (!1103)
 - randomize record order by default, i.e. reorder_RR(true) (!1123)
+- avoid excessive logging of UDP replies with sendmmsg (!1138)
 
 Bugfixes
 --------

diff --git a/daemon/udp_queue.c b/daemon/udp_queue.c
index 9cf39401a39c8b4f4816090c9c4edf4e20920b15..4d2f27ae9758956b000a90382b8dd974e316af53 100644 (file)
--- a/daemon/udp_queue.c
+++ b/daemon/udp_queue.c
@@ -76,19 +76,6 @@ static void udp_queue_send(int fd)
        int sent_len = sendmmsg(fd, q->msgvec, q->len, 0);
        /* ATM we don't really do anything about failures. */
        int err = sent_len < 0 ? errno : EAGAIN /* unknown error, really */;
-       if (unlikely(sent_len != q->len)) {
-               if (err != EWOULDBLOCK) {
-                       kr_log_error("ERROR: udp sendmmsg() sent %d / %d; %s\n",
-                                       sent_len, q->len, strerror(err));
-               } else {
-                       const uint64_t stamp_now = kr_now();
-                       static uint64_t stamp_last = 0;
-                       if (stamp_now > stamp_last + 60*1000) {
-                               kr_log_info("WARNING: dropped UDP reply packet(s) due to network overload (reported at most once per minute)\n");
-                               stamp_last = stamp_now;
-                       }
-               }
-       }
        for (int i = 0; i < q->len; ++i) {
                qr_task_on_send(q->items[i].task, NULL, i < sent_len ? 0 : err);
                worker_task_unref(q->items[i].task);