diff --git a/smmapdfw/libsmmapdfw/dns.c b/smmapdfw/libsmmapdfw/dns.c
index 44ab2ae..160365e 100644
--- a/smmapdfw/libsmmapdfw/dns.c
+++ b/smmapdfw/libsmmapdfw/dns.c
@@ -166,6 +166,7 @@ static void** get_rrs(char *domain, int qtype) {
 
   res = res_search(domain, C_IN, qtype, (u_char*) &answer, sizeof(answer_t));
   if (-1 == res) {
+    syslog(LOG_ERR, "get_rrs: error in res_search: h_errno=%d, errno=%d", h_errno, errno);
     return NULL;
   }