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Comment: Migration of unmigrated content due to installation of a new plugin

...

You

...

can

...

run

...

fireworks

...

(cmsShow)

...

on

...

your

...

laptop

...

or

...

desktop

...

machine

...

and

...

access

...

data

...

directly

...

from

...

our

...

Tier-2

...

dCache.

...


Just

...

put

...

the

...

prefix

...

'root://dcache-00.rcac.purdue.edu/pnfs/rcac.purdue.edu/data/'

...

in

...

front

...

of

...

the

...

LFN.

...

Example:

...

:}
Code Block
xml
xml
> cmsShow root://dcache-00.rcac.purdue.edu/pnfs/rcac.purdue.edu/data/store/data/BeamCommissioning09/MinimumBias/RAW-RECO/SD_AllMinBias-Jan23Skim-v1/0014/AC5CE429-B809-DF11-85F1-0026189438A9.root
{code}

To

...

copy

...

a

...

single

...

file

...

from

...

the

...

Tier-2

...

dCache

...

to

...

your

...

local

...

machine

...

(laptop

...

or

...

desktop)

...

you

...

can

...

use

...

the

...

command

...

xrdcp

...

.

...


First

...

you

...

need

...

to

...

initialize

...

your

...

ROOT

...

or

...

CMSSW

...

environment

...

(run

...

cmsenv).

...

Example:

...

:}
Code Block
xml
xml
> xrdcp root://xrootd.rcac.purdue.edu//store/group/ewk/DY/DYM20/ntuple_skim_96_2_z5w.root my.root
{code}

You

...

will

...

get

...

a

...

progress

...

bar

...

as

...

the

...

file

...

downloads.

...

You

...

may

...

also

...

want

...

to

...

think

...

about

...

using

...

the

...

-R

...

option,

...

which

...

allows

...

you

...

to

...

recursively

...

download

...

a

...

directory.

...


Please

...

see

...

the

...

details

...

at

...

https://twiki.opensciencegrid.org/bin/view/Tier3/XrootdClient

...

If

...

you

...

are

...

using

...

ROOT,

...

you

...

can

...

open

...

files

...

from

...

our

...

Tier-2

...

dCache

...

just

...

like

...

you

...

would

...

any

...

other

...

file:

...

:}
Code Block
xml
xml
TFile::Open("root://dcache-00.rcac.purdue.edu/pnfs/rcac.purdue.edu/data/store/data/BeamCommissioning09/MinimumBias/RAW-RECO/SD_AllMinBias-Jan23Skim-v1/0014/AC5CE429-B809-DF11-85F1-0026189438A9.root");
{code}

This

...

returns

...

a

...

TFile

...

object,

...

and

...

you

...

can

...

proceed

...

normally.

...

 

Data access through AAA:

Check for file availability with:

Code Block
xml
xml
> xrd cms-xrd-global.cern.ch existfile /store/myfile.root 
{code}

Direct

...

access:

...

ROOT

...

and

...

CMSSW

...

PoolSource

...

can

...

open

...

a

...

remote

...

file

...

directly

...

through

...

AAA

...

:}
Code Block
xml
xml
> “root://cms-xrd-global.cern.ch//store/myfile.root” 
{code}

Make

...

a

...

local

...

copy:

...

:}
Code Block
xml
xml
> xrdcp root://cms-xrd-global.cern.ch//store/myfile.root /localpath/myfile.root 
{code}

For

...

additional

...

information

...

see:

...

https://twiki.cern.ch/twiki/bin/view/CMSPublic/WorkBookXrootdService

...