[ovs-dev] [PATCHv5] DNS: Add basic support for asynchronous DNS resolving

[Shashank Ram]

On Tue, Jun 26, 2018 at 7:08 PM Yifeng Sun <pkusunyifeng at gmail.com> wrote:

> This patch is a simple implementation for the proposal discussed in
>
> https://mail.openvswitch.org/pipermail/ovs-dev/2017-August/337038.html
> and
> https://mail.openvswitch.org/pipermail/ovs-dev/2017-October/340013.html.
>
>
> It enables ovs-vswitchd and other utilities to use DNS names when
> specifying
> OpenFlow and OVSDB remotes.
>
>
> Below are some of the features and limitations of this patch:
>
>     - Resolving is asynchornous in daemon context, avoiding blocking main
> loop;
>     - Resolving is synchronous in general utility context;
>
>     - Both IPv4 and IPv6 are supported;
>
>     - The resolving API is thread-safe;
>
>     - Depends on the unbound library;
>
>     - When multiple ip addresses are returned, only the first one is
> used;
>     - /etc/nsswitch.conf isn't respected as unbound library doesn't look
> at it;
>     - For async-resolving, caller need to retry later; there is no
> callback.
>
> Signed-off-by: Yifeng Sun <pkusunyifeng at gmail.com>
> ---
>

Could you consider using the asynchronous DnsQuerEx() API for Windows?
https://docs.microsoft.com/en-us/windows/desktop/api/windns/nf-windns-dnsqueryex

Thanks,
Shashank