Thnakyou all for information about xrootd. The D-Cache team would love the results to be verified as they have difficulty accepting that thier xrootd server could run faster than xrootd native server and suspect that maybe you have optimised your dcache more than the xrootd server?
Thankyou both Kostas and Chris for pointing out quite correctly that the xrootd door does not yet have authentication and cannot yet be configured to support readonly access.
I have requested from the dcache team that they make a change to the door configuration so that the xrootd door supports read only access and can be configured with read only access. They are pleased to say this change will be done very soon and is now a high priority, and a new beta dcache xrootd rpm will come in the near future. We discussed errors, and they dont yet know what sort of errors they will get from the clients when readonly access is configured from the client that trys to write as they do not control an xrootd client code.
Thier maybe a longer wait for security on xrootd as the Dcache tream have no knowlage about xrootd and this protocol with repect to security, do you guys know who to contact to find out about how xrootd security should/is implemented.
Regards
Owen
PS
RAL's M$ web client has no spell check so sorry for typos etc
-----Original Message-----
From: GRIDPP2: Deployment and support of SRM and local storage management on behalf of Brew, CAJ (Chris)
Sent: Thu 6/1/2006 12:19 PM
To: [log in to unmask]
Subject: Re: dCache and xrootd
Hi Owen,
Simple file access test comparing accessing 2.4GB babar collection (2
files - 1.6GB and 800MB) from normal xrootd setup and from dCache via
xrootd door using 'time'
xrootd
------
real 15m27.020s
user 10m10.470s
sys 0m17.620s
dCache over xroot
-----------------
real 11m37.365s
user 9m44.490s
sys 0m14.300s
I can't really hammer it since it's running on my production system but
I'll try to do a couple of slightly heavier tests and post the results.
Could you ask if there's a way to configure it read only?
Yours,
Chris.
> -----Original Message-----
> From: GRIDPP2: Deployment and support of SRM and local
> storage management [mailto:[log in to unmask]] On
> Behalf Of Synge, OM (Owen)
> Sent: 01 June 2006 11:45
> To: [log in to unmask]
> Subject: Re: dCache and xrootd
>
> I just told the D-Cache team, and they where delighted that
> things have not yet broken for you, thier instant answer was
> can we have performance numbers
>
> So please when you have got more results tell us all and I
> will pass on your good new to D-Cache.
>
> Patrick also asked if he could quote you as having installed
> xrootd for D-Cache.
>
> I guess that will have to wait a little, until all the tests are run
>
> Regards
>
> Owen
>
>
> PS
>
> M$ web access has no spell check so sorry for my spelling
>
> -----Original Message-----
> From: GRIDPP2: Deployment and support of SRM and local
> storage management on behalf of Brew, CAJ (Chris)
> Sent: Wed 5/31/2006 5:24 PM
> To: [log in to unmask]
> Subject: Re: dCache and xrootd
>
> Hi,
>
> Having just fixed my other problems on my dCache system I
> thought I'd create some more for myself.
>
> But disappointingly this just seems to work. Installation was
> as per this instructions and straight away I was able to run
> some of the BaBar tools against it.
>
> I'll run a few more tests against it but so far it looks good.
>
> Chris.
>
> One more step in BaBar's plan for world domination done. Mwahahahah!
>
> > -----Original Message-----
> > From: GRIDPP2: Deployment and support of SRM and local storage
> > management [mailto:[log in to unmask]] On Behalf
> Of Greig A
> > Cowan
> > Sent: 31 May 2006 09:46
> > To: [log in to unmask]
> > Subject: dCache and xrootd
> >
> > Hi all,
> >
> > Just to let you know that you can now get your hands on the
> > (beta) xrootd
> > door to dCache. Download the tarball from here:
> >
> > http://www.dcache.org/downloads/releases/dcache-xrootd-0.9beta.tar
> >
> > Looking at the installation notes, it is relatively trivial to
> > install, just drop it into /opt/d-cache on each of your
> dCache nodes,
> > configure a file, restart dcache-core and -pool, and then
> open up the
> > xrootd door on the node(s) that you want to run it on:
> >
> > /opt/d-cache/jobs/xrootdDoor start
> >
> > It is not yet integrated into YAIM, but Owen may be working on that
> > while he is in DESY.
> >
> > Note that they claim it is a beta release, so only a subset of the
> > xrootd protocol has been implemented and xrootd transfers are not
> > authenticated.
> > I haven't been able to try it yet since I do not have ROOT
> installed
> > on any nodes.
> >
> > Let me know how you get on if you give it a go.
> >
> > dCache-xrootd 0.9beta release notes:
> >
> > -extends dCache to offer file transfer based on the Xrootd protocol
> > -allows access of dCache files (read/write, random access)
> from within
> > ROOT in a transparent way -implements current Xrootd
> protocol version
> > 2.4.5 (production) -tested with TXNetFile (main
> xrootd-client as it is
> > found in the latest ROOT version) and xrdcp (also contained in the
> > ROOT distribution)
> >
> > -requirements:
> > #running dCache instance (production version 1.6.6)
> >
> >
> > -limitations:
> > # only a small subset (the main xrootd messages like login,
> > open, read, write, close) of the Xrootd protocol is
> implemented so far
> > # async file transfer not yet supported (the
> kXR_async flag in
> > open requests will be ignored by now)
> > # authentitication not yet implemented (no access
> control at
> > the
> > moment)
> >
> >
> > Cheers,
> > Greig
> >
> > --
> > ==============================================================
> > ==========
> > Dr Greig A Cowan
> > http://www.ph.ed.ac.uk/~gcowan1
> > School of Physics, University of Edinburgh, James Clerk Maxwell
> > Building
> >
> > TIER-2 STORAGE SUPPORT PAGES:
> > http://wiki.gridpp.ac.uk/wiki/Grid_Storage
> > ==============================================================
> > ==========
> >
>
|