stop building chain if no server are reachable
stop building chain if no server are reachable


NLnetLabs/ldns,NLnetLabs/ldns,gegenschall/ldns,NLnetLabs/ldns,benlaurie/ldns,NLnetLabs/ldns,gegenschall/ldns,threatstack/libldns,threatstack/libldns,benlaurie/ldns,gegenschall/ldns,gegenschall/ldns,benlaurie/ldns,benlaurie/ldns,threatstack/libldns,threatstack/libldns,threatstack/libldns