1. The Disk Resource Manager A Berkeley SRM for Disk Cache Implementation and Testing Experience on the OSG Jorge Luis Rodriguez IBP/Grid Mini-Workshop Apr 7-8, 2005

2. 4/7/2005Jorge L. Rodriguez2 Storage in Grid3 No real Storage Element in Grid3 Defined a set storage locations to enable jobs to run at a site –The middleware location $Grid3: sharing recommended, the $VDT_LOCATION –Shared across the entire CE and chmod = 0777  $APP: Applications are installed here $DATA: Users scratch space lifetime ~ per exp. run $TMP: Another user scratch space, lifetime ~ per job –Non-shared local to worker nodes $WNTMP: Also chmod 0777, lifetime ~ per job Very simplistic but something was needed to get us off the ground On the CE

3. 4/7/2005Jorge L. Rodriguez3 DRM Service Deployment Goals To provide managed “tactical” storage to an OSG site –Apply SRM interface to $DATA… shared space –Storage space reservation –Storage request scheduling Should function in the OSG environment –OSG Packaging pacman –OSG MIS Publish relevant service parameters (port #s, Service names…) –OSG Authorization Multi-VO, VOMS managed gridmap-file

4. 4/7/2005Jorge L. Rodriguez4 Service Description Brief overview of the DRM Service –CORBA based service Based on SRM v.1.1 specification Movement of files into and out of SRM cache Default Lifetime, space quota, caching and queuing policies are supported Can be used through command-line DRM clients –Web Service component is provided by JAVA based wrapper interoperable with other SRMs (e.g. dCache- SRM) Can be used through srmcp fermilab client

5. 4/7/2005Jorge L. Rodriguez5 Service Description DRM dependencies –Functions on top of ordinary UNIX file systems: local, NFS… –Binaries available for RH7.x and RHEL 3 –Statically linked and self contained Requires JAVA 1.4+ Requires data movement services: gTK, gsiftp

6. Working in the OSG

7. 4/7/2005Jorge L. Rodriguez7 Enterprise Technical Groups Research Grid Projects VOs Researchers Sites Service Providers Labs activity 1 activity 1 activity 1 Activities Advisory Committee Core OSG Staff (few FTEs, manager) OSG Council (all members above a certain threshold, Chair, officers) Executive Board (8-15 representatives Chair, Officers) OSG Organization

8. 4/7/2005Jorge L. Rodriguez8 Privilegec TG-Storage OSG deployment Monitoring DRM The DRM Activity UFlorida LBL Argonne Vanderbilt FNAL Integration Privilegec Privilege Documents Readiness Plan Testbed Plone website

9. 4/7/2005Jorge L. Rodriguez9 The DRM Activity Readiness Plan –Details what we plan to do to get the service ready for deployment in the OSG –Examine deployment strategies Deploy with other CE services Deploy as stand alone service (on separate host) –Examine impact on other OSG services Authorization, monitoring, packagin… –Develop testing alogrithum Include service verification Include mock up and real application tests

10. 4/7/2005Jorge L. Rodriguez10 The DRM Activity Logistics and Documentation –Telecon meetings on a semi-regular basis –e-mail list osg-drm@opensciencegrid.orgosg-drm@opensciencegrid.org Plone website plone.opensciencegrid.org –Installation instructions –Meetings and minutes –Collection of interesting document –DRM testbed site information

11. Installation and Configuration

12. 4/7/2005Jorge L. Rodriguez12 Installation DRM is included a part of VDT1.3.3+ –DRM vers 1.2.4 in the VDT –The CORBA components are installed and configured by the VDT Can be deployed with everything else… –How its currently deployed in DRM testbed –Canonical Grid3 site… Can also be deployed stand alone –VDT will handle dependencies –Also being tried in DRM testbed

13. 4/7/2005Jorge L. Rodriguez13 Configuration Should install as a non-privileged user (srm) –Service provider recommends this for security reasons File system configuration –These recommendations are a work in progress! –Allocate a separate partition for the cache –RW for the service uid, all others RO Can and should use service certificates Auto configuration and sysV startup script included –Hand entered parameters will likely be required –Web Service configuration is now working

14. Testing and Validation

15. 4/7/2005Jorge L. Rodriguez15 Site Level Testing CORBA and Java Web Services are running Simple File movement exercise –Move files into and out of the DRM cache via the SRM interface –Move files into and out of from a remote DRM client –Move files into and out of DRM cache from a remote SRM-dCache client DRM test harness (from LBL team) –Included with DRM vers 1.2.4+ –Will be part of the overall site verification

16. 4/7/2005Jorge L. Rodriguez16 Application Level Test Simplified (mockup) application test will include: 1.stage file into DRM cache from remote DRM/SRM-dCache client 2.Execute job that access “staged in” file in DRM cache via POSIX calls 3.Job creates an output file on local storage ($WNTMP or $TMP) 4.Job moves file from local storage into local DRM cache 5.Job moves file from DRM cache to SRM managed or regular remote location Testing by real Application(s) –Make and document recommendations for use of DRM services in job work flow –Make DRM enabled sites available for application testers Schedule with application administrators Monitor activity by both site and application administrators

17. 4/7/2005Jorge L. Rodriguez17 Service Monitoring Will need input from Service Provider as to what to monitor and what to measure Performance of storage requests –How does the reservation system work –How does storage request scheduling function Resource load from DRM activities –Impact on server load –Impact on other running services

18. Pending Issues & Next Steps

19. 4/7/2005Jorge L. Rodriguez19 Where are We Now? DRM will NOT be ready for OSG-0 –Service was deployed on two OSG based sites –Could not complete simple service operational exercises in time for OSG deployment decision Need more “user” effort (testbed…) Dependency on other services critical Service difficult to use due to lack of documentation Ongoing service development, changes and new significant new features between versions Will try for next OSG relase –OSG integration is very busy with other services anyway…

20. 4/7/2005Jorge L. Rodriguez20 Where Are We Now? Communication channels created –plone activity, email lists and meetings –Coordinating with OSG-TG Four sites in the readiness tesbed –Argonne: Ed May –Buffalo: Mark Green –Florida: Jorge Rodriguez –LBL: Alex Sim (DRM developers)

21. 4/7/2005Jorge L. Rodriguez21 Where Are We Now? Activities now focused on using DRM software –CORBA services installed and used Exercised file movement with gsiftp and SRM Files moved into DRM cache worked OK Problems with new/old proxies –Web Services All of these are now up and running out of the box So far only experts have operated the service using these Need to continue going through the procedures outlined in the readiness

22. 4/7/2005Jorge L. Rodriguez22 Next Steps Continue to work out kinks in the installation and configuration procedures Feed those back into the VDT packaging Run through the testing and validation steps outlined in slides 8 through 11 Understand, document and communicate the service functionality: –To OSG site admins: Impact on an individual site and services Impact on OSG grid wide services –To OSG application community: How will it impact on previously used work flows? What other changes are needed effectively use the new services?