Le 19/01/2018 à 06:10, D. R. Evans a écrit :
Pascal Hambourg wrote on 01/18/2018 02:41 PM:Note : ping is not a proper DNS tool becaus it calls the libc resolver for name resolution, which may use other name sources than DNS. Use dig, host or nslookup instead.I admit that I'm quite surprised that everything doesn't use the libc resolver (by which I assume you mean the operations performed by gethostbyname() or something equivalent). I should look at the code for dig or nslookup sometime to see how they resolve names.
DNS tools directly send DNS queries to the specified nameserver. They may use the libc resolver only to resolve the nameserver hostname (if the nameserver is specified by hostname) or get the nameserver address list from /etc/resolv.conf (if a nameserver is not specified).