[ovs-git] [openvswitch/ovs] 771680: DNS: Add basic support for asynchronous DNS resolv...

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/openvswitch/ovs
  Commit: 771680d96fb6f996987630cb85bb749478512268
      https://github.com/openvswitch/ovs/commit/771680d96fb6f996987630cb85bb749478512268
  Author: Yifeng Sun <pkusunyifeng at gmail.com>
  Date:   2018-07-06 (Fri, 06 Jul 2018)

  Changed paths:
    M .travis.yml
    M Documentation/intro/install/general.rst
    M Documentation/ref/ovsdb.7.rst
    M NEWS
    M configure.ac
    M debian/control
    M lib/automake.mk
    A lib/dns-resolve-stub.c
    A lib/dns-resolve.c
    A lib/dns-resolve.h
    M lib/socket-util.c
    M lib/stream.c
    M lib/vconn-active.man
    M lib/vconn-passive.man
    M lib/vconn.c
    M m4/openvswitch.m4
    M ovn/controller-vtep/ovn-controller-vtep.8.xml
    M ovn/ovn-nb.xml
    M ovn/ovn-sb.xml
    M python/ovs/stream.py
    M rhel/openvswitch-fedora.spec.in
    M rhel/openvswitch.spec.in
    M vswitchd/ovs-vswitchd.c
    M vswitchd/vswitch.xml
    M vtep/vtep.xml

  Log Message:
  -----------
  DNS: Add basic support for asynchronous DNS resolving

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>
Signed-off-by: Ben Pfaff <blp at ovn.org>



      **NOTE:** This service been marked for deprecation: https://developer.github.com/changes/2018-04-25-github-services-deprecation/

      Functionality will be removed from GitHub.com on January 31st, 2019.