[ovs-dev] [PATCH v4 0/6] Add minimum network namespace support.

[Ben Pfaff]

On Thu, Mar 29, 2018 at 11:05:25PM -0300, Flavio Leitner wrote:
> Today Open vSwitch doesn't know about network namespaces (netns), but
> users are moving internal ports to other namespaces.  Although packets
> are still flowing, the daemon fails to find out basic port information,
> like if it is UP or DOWN, for instance.
> 
> This patchset rely on a new kernel vport API recently accepted to find
> out the new network namespace ID of a bridge's port. This information
> along with the port's name recorded in the database is used to match the
> corresponding netlink messages.
> 
> This patchset also leverages another kernel API that allows the daemon
> to listen to all netlink messages from all netns which has an ID assigned
> into it.  This and the previous change allows the userspace to track ports
> in other network namespaces.
> 
> If any of the APIs aren't available, it falls back to the older APIs to
> not break backwards compatibility.

I applied this to master.  Thank you!

I have a request: please submit a patch to add something to NEWS to
explain the new features.

I also have some further thoughts.

First, this patch has an aspect of trying a newer interface then falling
back to an older one.  I did not read the code carefully enough this
time (and do not remember from before) to figure out whether this is
likely to be a performance problem with older kernels.  If it is, that
might bear some improvement.

Second, I think that it is possible to open a Netlink socket for a
particular namespace, which might provide a way to do arbitrary Netlink
operations in a namespace even if the API doesn't support a namespace ID
as a parameter.