[ovs-dev] [PATCH] PORTING: Add hint to adjust the default fail-mode, for hardware ports.

[Ben Pfaff]

Thanks Rob, I pushed this to master.

On Wed, May 16, 2012 at 12:57:20PM -0700, Rob Sherwood wrote:
> Patch looks great Ben -- thanks for looking into this.
> 
> - Rob
> .
> 
> On Wed, May 16, 2012 at 12:44 PM, Ben Pfaff <blp at nicira.com> wrote:
> > Suggested-by: Rob Sherwood <rob.sherwood at bigswitch.com>
> > Signed-off-by: Ben Pfaff <blp at nicira.com>
> > ---
> >  PORTING |   11 +++++++++++
> >  1 files changed, 11 insertions(+), 0 deletions(-)
> >
> > diff --git a/PORTING b/PORTING
> > index 5281d50..ffde296 100644
> > --- a/PORTING
> > +++ b/PORTING
> > @@ -245,6 +245,17 @@ ovs_be64 as fixed-width types in network byte order.  Each of the
> >  latter is equivalent to the one of the former, but the difference in
> >  name makes the intended use obvious.
> >
> > +The default "fail-mode" for Open vSwitch bridges is "standalone",
> > +meaning that, when the OpenFlow controllers cannot be contacted, Open
> > +vSwitch acts as a regular MAC-learning switch.  This works well in
> > +virtualization environments where there is normally just one uplink
> > +(either a single physical interface or a bond).  In a more general
> > +environment, it can create loops.  So, if you are porting to a
> > +general-purpose switch platform, you should consider changing the
> > +default "fail-mode" to "secure", which does not behave this way.  See
> > +documentation for the "fail-mode" column in the Bridge table in
> > +ovs-vswitchd.conf.db(5) for more information.
> > +
> >  lib/entropy.c assumes that it can obtain high-quality random number
> >  seeds at startup by reading from /dev/urandom.  You will need to
> >  modify it if this is not true on your platform.
> > --
> > 1.7.2.5
> >