[ovs-git] [openvswitch/ovs] 8dd5b5: ovn-northd: Allow static routes with nexthop in di...

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/openvswitch/ovs
  Commit: 8dd5b5123f5ab2106d35a37235dd94767130a94e
      https://github.com/openvswitch/ovs/commit/8dd5b5123f5ab2106d35a37235dd94767130a94e
  Author: Guru Shetty <guru at ovn.org>
  Date:   2017-04-21 (Fri, 21 Apr 2017)

  Changed paths:
    M ovn/northd/ovn-northd.c
    M ovn/ovn-nb.xml

  Log Message:
  -----------
  ovn-northd: Allow static routes with nexthop in different subnet.

There are cases where the default gateway of a interface is in
a different subnet than its IP address. Linux allows such
configuration. For e.g, one could set the IP address of
a Linux interface as 172.16.1.2/32 and then give it a default
gateway of 172.16.1.1.  This can be done for e.g. by running the
following commands.

ifconfig eth0 172.16.1.2 netmask 255.255.255.255 broadcast 172.16.1.2
route add 172.16.1.1 dev eth0
route add default gw 172.16.1.1

The above configuration is what google cloud uses for its VMs.

In OVN static routes, we currently have the ability to specify the
router port via which the packet needs to be pushed out to reach a
next hop.  But when support for IPv6 was added, we only allowed
nexthops to be in the same subnet as one of the router's IP addresses.

This commit relaxes that restriction. When a outport is specified in
static routes and when a nexthop is in a different subnet than any
of the router IP addresses, we will assume that it is reachable from
the first IP address of the router.  Since this is a corner case,
we just go with the first IP address.  If it turns out that there
are more cases, we can let users choose the IP address via which
the destination is reachable.

Signed-off-by: Gurucharan Shetty <guru at ovn.org>
Acked-by: Ben Pfaff <blp at ovn.org>


  Commit: 6b785fd8fe29ecd41d4707f818cfff8870d5f790
      https://github.com/openvswitch/ovs/commit/6b785fd8fe29ecd41d4707f818cfff8870d5f790
  Author: Guru Shetty <guru at ovn.org>
  Date:   2017-04-21 (Fri, 21 Apr 2017)

  Changed paths:
    M ovn/lib/ovn-util.c
    M tests/ovn.at

  Log Message:
  -----------
  ovn-util: Allow /32 IP addresses for router ports.

On Google cloud, a VM gets a /32 IP address. When OVN
is deployed on such VMs, the OVN gateway router's IP
address becomes a /32 IP address. This commit allows
such a configuration.

Signed-off-by: Gurucharan Shetty <guru at ovn.org>
Acked-by: Ben Pfaff <blp at ovn.org>


Compare: https://github.com/openvswitch/ovs/compare/f73b83fd97d3...6b785fd8fe29