On Tue, 2005-02-22 at 14:55 +0000, Alessandra Forti wrote:
> > Because data is transfered to and from these servers over the internet.
>
> So it skips head node and gridftp servers second layer (in the tier1
> architecture) as explained by Andrew few mails ago?
The process is as follows,
{A} Client contacts server and asks where to put the data
{B} Client Receive a "Transfer" URL which is where to place the data
{C} Client uploads the data to URL.
Regards
Owen
> On Tue, 22 Feb 2005, Owen Synge wrote:
>
> > On Tue, 2005-02-22 at 14:41 +0000, Alessandra Forti wrote:
> >> So if there is no difference why using srmcp you need the data servers
> >> exposed to the internet?
> >
> >
> >> Are they SRMs themselves?
> >
> > No they are part of the SRM system but SRM its self is a redirecting API
> > which returns URL's to the data server.
> >
> >> Pehaps I haven't
> >> understood what an SRM is. I thought dcache was one of the SRMs, is it
> >> not?
> >
> > Dcache provides an SRM API and data servers to support SRM use so I
> > should say it is.
> >
> > Owen
> >
> >>
> >> cheers
> >> alessandra
> >>
> >> On Tue, 22 Feb 2005, Steve Traylen wrote:
> >>
> >>> On Tue, Feb 22, 2005 at 02:14:56PM +0000 or thereabouts, Owen Synge wrote:
> >>>> On Tue, 2005-02-22 at 14:05 +0000, Alessandra Forti wrote:
> >>>>> Hi Steve,
> >>>>>
> >>>>> as usual we are not talking the same language :) and I need a bit of
> >>>>> explanation.
> >>>>>
> >>>>>> I think everything is correct. Only addition is that the difference between
> >>>>>> CMS and the data challenge is that CMS do srmcp's where as the service
> >>>>>> challenge does a (get-turl && get-turl) , 3rd party g-u-c,
> >>>>>> (close-turl && close-turl). This is why the disk servers them selves
> >>>>>> must be exposed to internet in the CMS case since it is them that do the
> >>>>>> transfer for you and they do it non-passivly.
> >>>>>
> >>>>> what package does srmcp belong?
> >>>>
> >>>> d-cache-client-1.0-34
> >>>>
> >>>>> what package do get-turl/3rd party g-u-c/close-turl belong?
> >>>>
> >>>> Any Srm client. So probably the experimental code for CMS is my guess in
> >>>> this case.
> >>>>
> >>>>> what does g-u-c mean?
> >>>>
> >>>> I am guessing Steve means Globus URL Copy
> >>>>
> >>>>> what is the difference between the two?
> >>>>
> >>>> srmcp is written in Java, the rest are in C/C++.
> >>>>
> >>>> srmcp supports dcap.
> >>>>
> >>>> Apart from that, some WSDL passing, and some other trivial stuff not
> >>>> much from my knowledge, can you add more Steve?
> >>>
> >>> Not much, The srmcp supports the SRM cp method where you can ask one
> >>> SRM to copy a file to another SRM on your behalf thus making the
> >>> transfer asyrchonous.
> >>>
> >>> lcg-rep does a (get-source-turl,get-dest-turl), 3rd party globus-url-copy,
> >>> (close-source-turl,close-dest-turl) and is sychronous.
> >>>
> >>> Steve
> >>>
> >>>
> >>>
> >>>>
> >>>> Owen
> >>>
> >>> --
> >>> Steve Traylen
> >>> [log in to unmask]
> >>> http://www.gridpp.ac.uk/
> >>>
> >>
> >> --
> >> ********************************************
> >> * Dr Alessandra Forti *
> >> * Technical Coordinator - NorthGrid Tier2 *
> >> * http://www.hep.man.ac.uk/u/aforti *
> >> ********************************************
> >
>
> --
> ********************************************
> * Dr Alessandra Forti *
> * Technical Coordinator - NorthGrid Tier2 *
> * http://www.hep.man.ac.uk/u/aforti *
> ********************************************
