Re: How to check what DNS server OS X is using to resolve a given name?
Re: How to check what DNS server OS X is using to resolve a given name?
- Subject: Re: How to check what DNS server OS X is using to resolve a given name?
- From: Josh Graessley <email@hidden>
- Date: Fri, 13 Jul 2012 07:07:41 -0700
You can use the full resolver code path with:
dns-sd -G v4v6 www.apple.com
You can run "sudo killall -INFO mDNSResponder" to dump state to the system log.
-josh
On Jul 13, 2012, at 4:18, Alexis Gallagher <email@hidden> wrote:
> Hi,
>
> I'd like to debug my DNS settings. What tool does OS X offer that will let me observe what DNS server the system is using to resolve a domain name?
>
> I would normally just call dig or nslookup but the man pages warn that "The dig command does not use the host name and address resolution or the DNS query routing mechanisms used by other processes running on Mac OS X". Similarly for nslookup. A little experimenting suggests the Lookup command in the Network Utility app seems to have similar problems.
>
> "scutil -r" will report if OS X can reach a host specified by domain name, but it doesn't tell me how it reaches it. Another problem with "scutil -r" is that it seems to be broken — right now, on my machine, "scutil -r" tells me that github.com is not reachable by name, even though Safari can reach it by name and "scutil -r" can reach it by IP address. So I'm not sure what to make of that.
>
> Similarly, I know that "scutil --dns" shows all the DNS resolvers, but my whole purpose here is to verify that a complicated resolver configuration is behaving as I expect. I want to be able to exercise the system and see what it's doing.
>
> My DNS setting is complex because I'm trying to route some DNS queries to nameservers in a VPN, and others to nameservers outside the VPN. To do this I need to add custom resolvers to /etc/resolver, some of which are there just to override resolvers defined by the VPN server and created by the OS X built-in VPN client.
>
> Thanks,
> Alexis
> _______________________________________________
> Do not post admin requests to the list. They will be ignored.
> Macnetworkprog mailing list (email@hidden)
> Help/Unsubscribe/Update your Subscription:
>
> This email sent to email@hidden
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Macnetworkprog mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden