> -----Original Message-----
> From: Testbed Support for GridPP member institutes [mailto:TB-
>
> I'm about to install a new CE and SE (lustre/storm) at Queen Mary.
>
> I'm going to start on the CE. I've read through the YAIM
documentation,
> but it doesn't really touch on what to do about having two CEs, so I
> thought I'd ask here.
>
It's mostly straightforward if you're got the existing CE and torque
server on separate systems, and almost as easy if you haven't. The
YAIM docs describe how to configure a CE with no torque server (you are
running torque?). As long as the CE_HOST and BATCH_SERVER variables in
site-info.def are set correctly it pretty much just works.
You will need different settings for CE_HOST on the two CEs; you can
either use two different site-info.defs, or, given that it's actually
just a bash script, you can have the site-info.def set different values
depending on what node it's run on.
> Specific issues are:
>
> Ensuring that different users don't get mapped to the same
accounts[1].
>
NFS mounting /etc/grid-security/gridmapdir is the normal way to go about
it, we've been using that setup at Oxford for a while now, and I pinched
the idea from Chris Brew at RALPPD.
> Any gotcha's?
>
You might need to hand tweak the permissions on the torque server so
that
both CEs are allowed to submit jobs; I don't think yaim gets that right
on its own.
> Any other tips (no doubt I'll be back with more questions)?
>
The CE's have a directory which stores the software area tags at
/opt/edg/var/info; since your CEs front the same nodes they will
obviously
have the same software available to the worker nodes, so the CE tags
directories need to be the same. We just NFS mount ours from (as it
happens)
the torque server along with gridmapdir, so once a software installation
has finished and tags one CE, the other one automatically starts
advertising
the new tag too.
Ewan
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