[openib-general] Re: IPoIB and lid change

[Hal Rosenstock]

On Sun, 2006-02-12 at 08:52, Michael S. Tsirkin wrote:
> Quoting Hal Rosenstock <halr at voltaire.com>:
> > > > > Hi, Roland!  One issue we have with IPoIB is that IPoIB may cache a
> > > > > remote node path for a long time. Remote LID may get changed e.g. if the
> > > > > SM is changed, and IPoIB might lose connectivity.
> > > > 
> > > > The remote LID may get changed for other reasons too without an SM
> > > > change (SM merge of 2 separate subnets). How can this be handled ?
> > > 
> > > Change the SM to trigger SM lid change for both subnets?
> > 
> > I think that's overly disruptive for the subnet whose SM didn't change.
> > There should be a gentler way...
> 
> So that another issue with IPoIB subnet spanning multiple IB subnets.
> The IPoIB spec already lists several of these.

I was referring to the subnet merge case. In the case of 2 IB subnets
within a single IPoIB subnet, there is another layer of this issue as
you point out.

-- Hal