在此输入代码...
在 2016年5月6日星期五 UTC+8上午9:43:50，Ben Noordhuis写道： > > On Thu, May 5, 2016 at 9:00 AM, Yun Feng Ma <[email protected] > <javascript:>> wrote: > > Hi everyone! > > > > The dns.resolve tries to send request to only the first nameserver in > > /etc/resolv.conf, and if the first nameserver fails to resolve the name, > > dns.resolve just returns and doesn't try to send request to the second > > nameserver. Is this work-as-design? > > > > Here is an example: the /etc/resolv.conf is like below in Linux: > > 75.2.4.5 > > 75.4.7.6 > > > > Run below codes: > > dns.resolve('demo1.sample.com','A',function(err, addresses) { > > console.log(err); > > console.log(addresses); > > }); > > > > The 'demo1.sample.com' is defined in the second nameserver (75.4.7.6), > so > > the above codes always failed, because the dns.resolve doesn't try to > call > > the second nameserver. > > > > I found nodejs has flag to control this: > > > https://github.com/nodejs/node/blob/master/deps/cares/src/ares_init.c#L255 > > seems like the default behaviour is only call the first nameserver, is > there > > any way to make dns.resolve to call all nameservers in /etc/resolv.conf > > until succeed? > > > > Thanks a lot. > > The second nameserver is only tried when the first one times out or > returns a malformed reply. If the first server replies with NXDOMAIN > (domain not found), the second one isn't contacted; that shouldn't be > necessary because DNS is a global registry after all. > Thanks, Ben, for the reply. In our environment, the first nameserver is our internal DNS server, which is used to resolve some internal domain names; the second nameserver is the public nameserver (like google DNS server 8.8.8.8), so this code dns.resolve('www.google.com','A',function(err, addresses) { }) will get failed, because the first nameserver returns NXDOMAIN for "www.google.com". Do you have any solution for this? Thanks. -- Job board: http://jobs.nodejs.org/ New group rules: https://gist.github.com/othiym23/9886289#file-moderation-policy-md Old group rules: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines --- You received this message because you are subscribed to the Google Groups "nodejs" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/nodejs/fc2151fc-c0fe-4126-bdd8-e9bedf3815b0%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
