Stephen,
In our case, we publish 1 queue for all of the supported EGEE VOs at the site,
with the appropriate access control on that queue. This should limit the
type of info provider explosion, and should probably be scalable for
the number of subclusters that we may want to support.
> The mapping is supposed to be (1 or more subclusters) -> (1 cluster) ->
> (1 or more CEs). Unfortunately the broker can't cope with more than 1
> subcluster per cluster, so if you want to publish like that you have to
> duplicate the cluster as well and have a separate set of queues. You can
> however keep everything attached to a single CE head node. This has been
> done by Steve Traylen:
>
> http://goc.grid.sinica.edu.tw/gocwiki/How_to_publish_different_memory_li
> mits_for_different_queues_on_the_same_CE
>
> The main downside is that if you wanted to represent lots of different
> subcluster configurations you would end up with a huge explosion of
> queues (atlas_short_bigmem_fast-cpu_debian ...) There is supposed to be
> a working group looking at doing this more efficiently, but don't hold
> your breath :)
DNS has scaled up resonably well, could the same basic conceptal model be applied?
For instance, you could have a primary source/info provider, with multiple secondary sources.
(I am not saying that such a change would be easy).
>> It might be possible to publish that this subcluster has no
>> outbound IP access (again Stephen, can you verify this?).
>
> You can publish it, but there's no guarantee that people will check it
> in their JDL as it's generally assumed to be there. Also various bits of
> the middleware assume outbound connectivity.
Does the inbound/oubound apply to the service nodes, all nodes or just the worker nodes?
If it is on a service node such as the CE, then it is reasonable to assume outbound,
but assuming outbound on a workernode is not so reasonable, and the middleware/application developers
should actually take that into account. I don't think that a site can be criticised because
of this, unless they have signed an SLA stipulating that they would provide outbound.
cheers,
John W
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