Hi Fabrizio,
Yes, that's what the protocol says. That is, there can be two opaque
segments. As were're just starting to use opaque information in "real life"
I'm sure we'll learn a thing or two on how to use it.
Andy
----- Original Message -----
From: "Fabrizio Furano" <[log in to unmask]>
To: "Andrew Hanushevsky" <[log in to unmask]>
Cc: "Andreas Joachim Peters" <[log in to unmask]>; "Derek Feichtinger"
<[log in to unmask]>; "Fons Rademakers" <[log in to unmask]>;
"xrootd mailing list" <[log in to unmask]>
Sent: Friday, April 29, 2005 4:08 AM
Subject: Re: olbd fails to learn when a file disappears from a leaf node,
but another copy still exists
> Hi Andy,
>
> Ok, this in my mind means that appending (or not) an opaque info to the
> arguments of a mv is left to the application.
>
> Anyway, the recovery protocol states that some opaque info has to be
> appended after an unsuccessful open. The code as it is now appends this
> info after the opaque info which is considered part of the file name. Is
> it ok for you?
>
> Fabrizio
>
> Andrew Hanushevsky wrote:
>> Hi Fabrizio,
>>
>> There is nothing in the protocol that prevents this. Since opaque
>> information is opaque and is always passed as part of a filename, xrootd
>> simply forwards that information without interpretation. They could be
>> the
>> same or different, depends on the application.
>>
>> Andy
>>
>> On Thu, 28 Apr 2005, Fabrizio Furano wrote:
>>
>>
>>>Hi,
>>>
>>> uhm. I see and don't see. Will it have two opaque parameters or the
>>>same parameter appended to each filename?
>>>
>>>Fabrizio
>>>
>>>Andy Hanushevsky wrote:
>>>
>>>>Hi Fabrizio,
>>>>
>>>>I think we all agree on that. The only "nit" is that rename will have
>>>>two opaque parameters that someone will need to make sense of.
>>>>
>>>>Andy
>>>>
>>>>----- Original Message ----- From: "Fabrizio Furano"
>>>><[log in to unmask]>
>>>>To: "Andrew Hanushevsky" <[log in to unmask]>
>>>>Cc: "Andreas Joachim Peters" <[log in to unmask]>; "Derek Feichtinger"
>>>><[log in to unmask]>; "Fons Rademakers"
>>>><[log in to unmask]>; "xrootd mailing list"
>>>><[log in to unmask]>
>>>>Sent: Wednesday, April 27, 2005 7:24 AM
>>>>Subject: Re: olbd fails to learn when a file disappears from a leaf
>>>>node, but another copy still exists
>>>>
>>>>
>>>>
>>>>>Hi,
>>>>>
>>>>> I argue from this that the opaque info passed e.g. through xrdcp must
>>>>>be passed for any request containing a filename, like Stat or Dirlist.
>>>>>Am I right?
>>>>>
>>>>>Fabrizio
>>>>>
>>>>>Andrew Hanushevsky wrote:
>>>>>
>>>>>
>>>>>>Hi Andreas,
>>>>>>
>>>>>>OK, so it would appear that we will need to extract out the
>>>>>>information
>>>>>>after the "?" and pass that as a separate parameter. I do that,
>>>>>>instead of
>>>>>>passing the complete url, so as to not re-implement searching for the
>>>>>>opaque information in every function. The called function, hoewver, is
>>>>>>responsible for making sense of the opaque information.
>>>>>>
>>>>>>That does mean changing most file system calls to include the opaque
>>>>>>parameter. That also solves the olbd issue in a unified way.
>>>>>>
>>>>>>Do we all agree to go that route?
>>>>>>
>>>>>>Andy
>>>>>>
>>>>>>On Tue, 26 Apr 2005, Andreas Joachim Peters wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>>As it is, it is absolutely fine for me. I would prefer, that the
>>>>>>>complete
>>>>>>>URL is always passed to any function and the function has to extract
>>>>>>>the part
>>>>>>>it needs. But as it is, it works perfectly for us.
>>>>>>>
>>>>>>>I use the following syntax:
>>>>>>>
>>>>>>>root://server.domain:port/<lfn>?&authz=<authorization block>
>>>>>>>
>>>>>>>Because even for a stat command it can be useful, that you can
>>>>>>>specify
>>>>>>>some environment variable like the stagepool the file is on.
>>>>>>>
>>>>>>>Cheers Andreas.
>>>>>>>
>>>>>>>
>>>>>
>
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