Adding pool

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Following are the necessary steps to add a new pool group (ie add a new experiment) to trdata. Following example is for smd experiment.

Set up pool on data machine

Assume we set data pool on data machine trdata05 (ssh root@trdata05).

Create the pool (with 600GB of space)

/opt/d-cache/bin/dcache pool create --size=600G /data/dcache/pool/smd_05_00 smd_05_00 trdata05_00PoolDomain

in smd_05_00 05 indicates this is trdata05 and 00 means the first data device on this machine.

the restart dcache

service dcache restart

Note: nothing in dcache prevents you from oversubscribing the space on a particular machine. Ie, you could allocate two pools with 15TB of space on a device with just 20TB of space overall. You need to check that yourself.

Configuration on trdata00

Next steps are on trdata00 (ssh root@trdata00)

First, if dcache PNFS is not mounted, mount it

mount -o intr,rw,noac,hard,nfsvers=3 trdata00:/pnfs /pnfs

Now create a local user, with the same UID as the experiments user account.

groupadd -g 6016 smd
adduser -u 6016 -g smd smd

Now create the top level directory in dcache for smd

/opt/d-cache/bin/ Mkdir /pnfs/ 
echo "data" | /opt/d-cache/bin/ Writetag /pnfs/ sGroup
echo "StoreName smd" | /opt/d-cache/bin/ Writetag /pnfs/ OSMTemplate

Check that this worked

# cd /pnfs/
# cat '.(tag)(OSMTemplate)'
StoreName smd
# cat '.(tag)(sGroup)'

Make the directory belong to the right user

/opt/d-cache/bin/ Chown /pnfs/ 6016
/opt/d-cache/bin/ Chgrp /pnfs/ 6016

Admin Configuration on trdata00

Now we do the last setup with the obscure dcache interface.

ssh -c blowfish -p 22223 -l admin trdata00

(there is a password...)

cd PoolManager
psu create pgroup smd-pgroup
psu create pool smd_05_00
psu addto pgroup smd-pgroup smd_05_00
psu removefrom pgroup default smd_05_00
psu create unit -store smd:data@osm
psu create ugroup smd-cond
psu addto ugroup smd-cond smd:data@osm
psu create link smd-link smd-cond
psu set link smd-link -readpref=10 -writepref=10 -cachepref=10 -p2ppread=-1
psu add link smd-link smd-pgroup


Finally test if it worked from some random DAQ machine

mkdir /daq/pnfs/
dccp /etc/exports /daq/pnfs/