File dnsmasq-servfail.patch of Package dnsmasq.19459
--- src/forward.c
+++ src/forward.c
@@ -817,7 +817,7 @@ void reply_query(int fd, int family, time_t now)
/* Note: if we send extra options in the EDNS0 header, we can't recreate
the query from the reply. */
- if (RCODE(header) == REFUSED &&
+ if ((RCODE(header) == REFUSED || RCODE(header) == SERVFAIL) &&
forward->forwardall == 0 &&
!(forward->flags & FREC_HAS_EXTRADATA))
/* for broken servers, attempt to send to another one. */