Hi all, I am new to glue schema. May I ask if I can publish SRB information with GLUE schema? Since the examples I saw are all gridftp. thanks a lot. Cheers, Shunde.
Shunde Zhang wrote:
Hi all,
I am new to glue schema. May I ask if I can publish SRB information with GLUE schema? Since the examples I saw are all gridftp. thanks a lot.
Cheers, Shunde.
Hi Shunde. For my 0.02, the answer is yes, sort of. I have actually looked into this very problem, although I haven't spent much time on it yet. I am not an SRB expert myself though, but I am working with people who are. The trick is, unsurprisingly, to pretend that SRB is a StorageElement, and I aim to come up with a recipe for doing that - provided we can make it work with GridPP/EGEE resources - if we can't, why bother? The main difficulty that I can think of is that many users have personal directories (er, collections) in SRB and it is not straightforward to make automated tools pick up the path from GLUE unless an SA is published for each person or something weird like that. So the real question is what you aim to achieve with it. SRB has its own control and data transfer protocols. To achieve interoperability you need a standard protocol like the gridftp interface developed by Argonne (I believe) which you can then publish as a data transfer protocol. The SRB world itself does not use GLUE - at least none of the SRB communities I know and work with. The UK National Grid Service for example has SRB resources and uses GLUE, but the GLUE is not used to publish the SRBs, they are set up independently via user's MdasEnv files. Hope this helps a bit. If you want to collaborate or do something specific feel free to contact me. Regards, --jens -- Dr Jens Jensen Rutherford Appleton Laboratory Science and Technology Facilities Council UK
Hi Jens, Sorry for the late response since I've been away for days. Thanks for your reply and it is very helpful. Can I ask if your SRB is a 'normal' one or it is installed with GSI support or with a gridftp interface? At this stage I just started looking at how to publish SRB to our MDS. but I cannot find fields to put SRB's zone, resource and SRB uses username/password so how I can use ACL to show who can use what resource. If possible, could you also give me a sample of GLUE xml with SRB information? thanks a lot. Cheers, Shunde. Quoting "Jensen, J (Jens)" <j.jensen@rl.ac.uk>:
Shunde Zhang wrote:
Hi all,
I am new to glue schema. May I ask if I can publish SRB information with GLUE schema? Since the examples I saw are all gridftp. thanks a lot.
Cheers, Shunde.
Hi Shunde.
For my 0.02, the answer is yes, sort of. I have actually looked into this very problem, although I haven't spent much time on it yet. I am not an SRB expert myself though, but I am working with people who are.
The trick is, unsurprisingly, to pretend that SRB is a StorageElement, and I aim to come up with a recipe for doing that - provided we can make it work with GridPP/EGEE resources - if we can't, why bother? The main difficulty that I can think of is that many users have personal directories (er, collections) in SRB and it is not straightforward to make automated tools pick up the path from GLUE unless an SA is published for each person or something weird like that.
So the real question is what you aim to achieve with it. SRB has its own control and data transfer protocols. To achieve interoperability you need a standard protocol like the gridftp interface developed by Argonne (I believe) which you can then publish as a data transfer protocol.
The SRB world itself does not use GLUE - at least none of the SRB communities I know and work with. The UK National Grid Service for example has SRB resources and uses GLUE, but the GLUE is not used to publish the SRBs, they are set up independently via user's MdasEnv files.
Hope this helps a bit. If you want to collaborate or do something specific feel free to contact me.
Regards, --jens
-- Dr Jens Jensen Rutherford Appleton Laboratory Science and Technology Facilities Council UK
Shunde Zhang wrote:
Hi Jens,
Sorry for the late response since I've been away for days.
No worries - I know this only too well.
Thanks for your reply and it is very helpful.
Oh, good.
Can I ask if your SRB is a 'normal' one or it is installed with GSI support or with a gridftp interface?
Er, both. (Apologies for going off topic for GLUE-WG) It uses a normal .MdasAuth file for authentication, but also has a gridftp server - which of course uses GSI. The S commands use ENCRYPT1.
At this stage I just started looking at how to publish SRB to our MDS. but I cannot find fields to put SRB's zone, resource and SRB uses username/password so how I can use ACL to show who can use what resource.
Right, in my case the gridftp server is connected to a single SRB resource which in turn is more or less dedicated to a single VO (it's actually a test account for a customer but we use it more for interoperability testing). I am told this is the limitation of the gridftp server: if you're writing, you can access only one resource. However, it fits well with GLUE because you publish an SA with a suitable SAPath for a single VO. At this stage we haven't tried relying on the ACBR for resolving the SRB but it should be possible.
If possible, could you also give me a sample of GLUE xml with SRB information? thanks a lot.
Do an ldapsearch on ldap://pps-bdii.cern.ch:2170 looking for the SE with hostname kisumu.esc.rl.ac.uk. This one works even with lcg-cr! It's there now (just checked) but Derek (our Tier 1 BDII admin among other things) has been talking about moving it over to production so he can test it with CASTOR. If you can't find it, try looking in the toplevel BDII for production. Regards, --jens
Hi Shunde, Everything is possible, it just depends on what you hope to achieve and what is required. If the SRB exposes an SRM interface and this is what the users are looking for then it should be possible to publish it. If you are wanting to just expose the gridftp interface then this should be possible too. Alternatively, if you are wanting to publish the SRB as a service then there are a number of possibility's. Publish the SRB using the generic service, see if the Stroage Schema works or define a schema specifically for the SRB if it is significantly different. The main purpose of the glue schema is to facilitate interoperability between the grid infrastructures. It is use case driven and hence we have to understand how the users are using SRB between the infrastructures. As soon as we understand these use cases it will be easier to work out what to do. Thanks Laurence Shunde Zhang wrote:
Hi all,
I am new to glue schema. May I ask if I can publish SRB information with GLUE schema? Since the examples I saw are all gridftp. thanks a lot.
Cheers, Shunde.
_______________________________________________ glue-wg mailing list glue-wg@ogf.org http://www.ogf.org/mailman/listinfo/glue-wg
Hi Laurence, Thanks for the reply. Can I ask how to put SRM interface onto SRB? Yes, we have sucessfully put gridftp interface on SRB. but we just want to publish 'authenic' SRB information to our MDS. if I make my own schema to do that, would it be a problem of using 3rd party software since other people only support the standard GLUE schema? thanks a lot. Cheers, Shunde. Quoting Laurence <Laurence.Field@cern.ch>:
Hi Shunde,
Everything is possible, it just depends on what you hope to achieve and what is required. If the SRB exposes an SRM interface and this is what the users are looking for then it should be possible to publish it. If you are wanting to just expose the gridftp interface then this should be possible too. Alternatively, if you are wanting to publish the SRB as a service then there are a number of possibility's. Publish the SRB using the generic service, see if the Stroage Schema works or define a schema specifically for the SRB if it is significantly different.
The main purpose of the glue schema is to facilitate interoperability between the grid infrastructures. It is use case driven and hence we have to understand how the users are using SRB between the infrastructures. As soon as we understand these use cases it will be easier to work out what to do.
Thanks
Laurence
Shunde Zhang wrote:
Hi all,
I am new to glue schema. May I ask if I can publish SRB information with GLUE schema? Since the examples I saw are all gridftp. thanks a lot.
Cheers, Shunde.
_______________________________________________ glue-wg mailing list glue-wg@ogf.org http://www.ogf.org/mailman/listinfo/glue-wg
Hi Shunde, It might be best if we discussed this over the phone. You can phone me on the following number. +41 22 76 74741. Thanks Laruence Shunde Zhang wrote:
Hi Laurence,
Thanks for the reply. Can I ask how to put SRM interface onto SRB? Yes, we have sucessfully put gridftp interface on SRB. but we just want to publish 'authenic' SRB information to our MDS. if I make my own schema to do that, would it be a problem of using 3rd party software since other people only support the standard GLUE schema? thanks a lot.
Cheers, Shunde.
Quoting Laurence <Laurence.Field@cern.ch>:
Hi Shunde,
Everything is possible, it just depends on what you hope to achieve and what is required. If the SRB exposes an SRM interface and this is what the users are looking for then it should be possible to publish it. If you are wanting to just expose the gridftp interface then this should be possible too. Alternatively, if you are wanting to publish the SRB as a service then there are a number of possibility's. Publish the SRB using the generic service, see if the Stroage Schema works or define a schema specifically for the SRB if it is significantly different.
The main purpose of the glue schema is to facilitate interoperability between the grid infrastructures. It is use case driven and hence we have to understand how the users are using SRB between the infrastructures. As soon as we understand these use cases it will be easier to work out what to do.
Thanks
Laurence
Shunde Zhang wrote:
Hi all,
I am new to glue schema. May I ask if I can publish SRB information with
GLUE
schema? Since the examples I saw are all gridftp. thanks a lot.
Cheers, Shunde.
_______________________________________________ glue-wg mailing list glue-wg@ogf.org http://www.ogf.org/mailman/listinfo/glue-wg
participants (3)
-
Jensen, J (Jens) -
Laurence -
Shunde Zhang