>It is theoretically possible to support all this on an IPoIB based >network. Multiple subnets, multiple routes to remote peers, ICMP >redirect, multiple IP addresses for each physical interface, yada yada >yada. But IMHO, the only way to do this would be to tie directly into >the existing routing, ARP, ICMP, etc... subsystems in Linux. Otherwise >you'll end up recreating a gigantic (and I mean GIGANTIC) amount of
The current implementation ties into the standard Linux ARP tables. If connections were made over TCP/IP, using IPoIB, then I don't think that there would be any issues. The issues only arise because of the desire to use TCP/IP network addresses over a non-TCP/IP network. >code. This belief is why I've been a proponent of mapping GIDs to one >and only one IP address and treating it for management purposes as the >equivalent of an IP address. Without this, the whole mechanism for >determining routes, etc.. breaks down. If you treat the GID like a MAC >address -- it breaks, because a MAC address can have multiple IP >addresses -- the observation that lead to the conclusion that ATS was >broken in the first place. We should be able to handle the case where a GID has multiple IP addresses bound to it. But even if we added a 1:1 restriction, the connection over IB issue still exists. >I know there is significant resistance to this idea, but I just don't >see how we get this generically resolved without binding the two >addressing schemes more closely. With the current binding, I just don't >think it works. Again, I don't think that the binding is the issue, so much as the desire to use an address for a protocol that isn't actually being used for communication. I don't view a GID as an IP address because we're not sending and receiving IP packets on the GID. IPoIB treats GIDs as only part of a MAC address, which I think is the proper view. Anyway, returning back to the original problem of connecting to an IB gateway if a given a destination IP address on a different subnet... I'm slowly convincing myself that either the CMA or AT should do this. (I believe that the ib_addr code will do this now, but still wasn't sure that we wanted it to.) - Sean _______________________________________________ openib-general mailing list openib-general@openib.org http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general