[openib-general] some IB multicast sendonly thoughts

[Hal Rosenstock]

On Tue, 2007-01-16 at 10:33, Or Gerlitz wrote:
> > 15.2.5.17.1 GROUP MEMBERSHIP
> 
> > An endport must specify the type of multicast subscription or deletion that
> > it wants. The MCMemberRecord:JoinState component indicates the
> > membership qualities a port wishes to add (in joining or creating a group)
> > or remove (in leaving a group). The meanings of the MCMember-
> > Record:JoinState bits are:
> 
> > • FullMember: Group messages are routed both to and from the port.
> > The port is considered a member for purposes of group creation and
> > deletion, i.e.: if no member ports with FullMember=1 remain, the
> > group may be deleted; otherwise it may not.
> 
> > • NonMember: Group messages are routed both to and from the port.
> > The port is not considered a member for purposes of group creation/
> > deletion.
> 
> > • SendOnlyNonMember: Group messages are only routed from the
> > port; none are routed to the port. The port is not considered a member
> > for purposes of group creation/deletion.
> 
> ....
> 
> > MCMemberRecord:JoinState.FullMember bit must be set to 1 in the SubnAdmSet()
> > request that creates a multicast group.
> 
> ...
> 
> OK, assuming my setup consists of:
> 
> +1 IB node doing only multicast TX on a group
> 
> +2 an IB/Ethernet gateway
> 
> 3+ Eth node doing only multicast RX on the equiv mac (forget manytoone)
> 
> The gateway design is to register for SA MGID IN/OUT traps and when it 
> gets MGID IN it joins the the mgroup as ***NonMember** etc
> 
> Now, since the TX node joins as SendOnlyNonMember the SA would never 
> create this group --> the TX node would never get MLID etc to create AH, 
> etc etc
> 
> ---> this setup is broken.
> 
> any thoughts and/or ideas would be welcome

I don't think it matters whether it is a gateway scenario as you
describe or just a pure IB network. The only thing that matters is the
sequencing of the transmitter and receiver; e.g. whether a receiver
creates the group prior to the send only transmitter.

In the case of the gateway, when the receiver starts on the ethernet
side, the gateway would need to know this via some protocol (e.g. IGMP)
and then join appropriately on the IB side.

-- Hal

> Or.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 	
> 
> 
> _______________________________________________
> openib-general mailing list
> openib-general at openib.org
> http://openib.org/mailman/listinfo/openib-general
> 
> To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
>