diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c index 6c0c7539c2..7d969ff0b7 100644 --- a/src/resolve/resolved-dns-transaction.c +++ b/src/resolve/resolved-dns-transaction.c @@ -911,9 +911,13 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) { /* Request failed, immediately try again with reduced features */ - if (t->current_feature_level <= DNS_SERVER_FEATURE_LEVEL_WORST) { - /* This was already at the lowest possible feature level? If so, we can't downgrade - * this transaction anymore, hence let's process the response, and accept the rcode. */ + if (t->current_feature_level <= DNS_SERVER_FEATURE_LEVEL_UDP) { + /* This was already at UDP feature level? If so, it doesn't make sense to downgrade + * this transaction anymore, hence let's process the response, and accept the + * rcode. Note that we don't retry on TCP, since that's a suitable way to mitigate + * packet loss, but is not going to give us better rcodes should we actually have + * managed to get them already at UDP level. */ + log_debug("Server returned error: %s", dns_rcode_to_string(DNS_PACKET_RCODE(p))); break; } @@ -1136,7 +1140,7 @@ static int dns_transaction_emit_udp(DnsTransaction *t) { return r; if (t->current_feature_level < DNS_SERVER_FEATURE_LEVEL_UDP) - return -EAGAIN; + return -EAGAIN; /* Sorry, can't do UDP, try TCP! */ if (!dns_server_dnssec_supported(t->server) && dns_type_is_dnssec(t->key->type)) return -EOPNOTSUPP;