Re: GID clarifications
Kanoj Sarcar <[email protected]>
| Newsgroups | gmane.ietf.ipoib |
|---|---|
| Message-ID | <[email protected]> |
Randy Presuhn wrote: > > Hi - > > ... > > I don't think this is the case - NAT is completely contained within > > Layer 3. It does not do any layer 2 munging as far as I can tell. I > > believe the comment was in relationship to IB subnets (you have to be > > very careful - as they only differ by a letter) > ... > > Thanks for the clarification. I'm happy as long as whatever > shows up in the MIB is sufficiently unique to prevent confusion. "Sufficiently unique" seems to be the key point here. If you consider any GID of any endport in one IBA subnet, or in a set of IBA subnets all connected by IBA routers, the GID is guaranteed to uniquely identify the endport (which is what I pointed out originally). > For example, consider what could happen when mutiple > enterprises outsource their network management to the > same provider. The management systems need to be able to > tell whether a given idententifier refers to the same or different > systems, particularly if the relationships between the enterprises > potentially involve shared facilities. If the provider is managing two unconnected sets of IBA subnets (simple example would be a single IBA subnet for A, and a single IBA subnet for B, not connected to each other), then two different endports might have the same GID; ie, by looking at the GID, you could not decide whether it referred to the endport in A or in B. This is true in general, but if everyone decided to always used GID index 0, then all GIDs are guaranteed to be unique (I think I see what the intent of the statement in the draft was). As Bill pointed out, NAT probably does not look at macaddress/GID to make this differentiation. If you believe you have some protocol or system that needs to differentiate based on the IPoIB macaddress/GID, you should bring it up to the list; it will add weight to the argument that everyone must be required to (as opposed to recommended to) use GID index 0. Thanks. Kanoj > > Randy > > _______________________________________________ > IPoverIB mailing list > [email protected] > https://www1.ietf.org/mailman/listinfo/ipoverib