LHC Computer Grid - Rollout
> [mailto:[log in to unmask]] On Behalf Of
> Andreas Gellrich said:
> We have started to look into installing/upgrading our Grid Testbed
> machines to gLite 3.0.1.
This is *not* an official reply, just some comments from an onlooker ...
> * Which type of Computing Element should be installed in LCG?
> In order to *just* upgrade the CEs and have them still connected to
> BDIIs and RBs as they are operated in LCG, a 'lcg-CE' is needed?
In practice you probably still want to have an LCG CE, but you may want
to try a glite CE as well.
> Does the glite-CE speak to BDIIs?
Yes, but there seems to be a problem with configuration of a site BDII
on the glite CE, so you probably need to run that on the LCG CE.
> * Does the WMS/LB replace the RBs?
Yes in theory, but we will probably have both types in the Grid for some
time.
> Can LCG CEs still be used with th WMS/LB?
You can use LCG CEs with the glite WMS, but you can't use glite CEs with
the LCG RB. Also, the glite UI commands (glite-job-*) are not entirely
backward-compatible, so you need to use glite-job-* with a glite WMS and
edg-job-* with an LCG RB.
> What is the role of a BDII then?
The new WMS can operate in various modes, but at the moment it's
configured in the same way as the old system, i.e. push mode with a
BDII.
> Is there supposed to be co-existence of RBs and WMS/LBs?
Yes, at least until the new WMS is proved to be stable enough.
Stephen
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