1. Duke and ANL ASC Tier 3 (stand alone Tier 3’s) Doug Benjamin Duke University

2. ANL ATLAS Analysis Center “prototype” Tier 3 Used to develop all of the scripts needed to setup a Tier 3 site – Used to test tools and software to train others Expect it to grow as the number of users at the ASC increases Developing puppet configurations at this site Supported by DPB (very part time) Use Xrootd.org Yum repository for most libraries OSG Yum repository for the gridftp bits

3. “baseline” Tier 3g public/private networks Head = redirector Standalone xrootd data server Xrootd data servers all on private network only Clustered xrootd storage

4. Head Node/Redire ctor Stand alone Xrootd data server worker Node/ xrootd data server Private network Xrootd clustered storage (private network) Baseline Tier 3 (public/private network) All data access within cluster (LAN) via private network Use case 2. – storage on worker node data servers as part of Federation Physical machine w/ local xrootd functionality Overlay xrootd functionality Public IP network Head node xrootd Proxy (public network) Head node xrootd Proxy (public network) Head node - Xrootd read-only redirector(private network) Xrootd read-only data server(private network) Outgoing read only data flow

5. Xrootd configuration Wiki page with example configuration https://twiki.cern.ch/twiki/bin/view/Atlas/Tier3gXrootdSetu p https://twiki.cern.ch/twiki/bin/view/Atlas/Tier3gXrootdSetu p Know issues “sss” xrootdfs Frm checksuming turned off - Due to configuration of the data servers (oss.localroot).

6. Duke Tier 3 Support Department system admin’s DPB (very part time) Puppet helps reduce the loads Disk heavy worker nodes and on big file server (SL 6) Stand alone SL 5 gridftp server (used a proxy server) Use Xrootd.org Yum repository for most libraries OSG Yum repository for the gridftp bits

7. Head Node/Redire ctor Stand alone Xrootd data server worker Node/ xrootd data server Xrootd clustered storage Public network version of Baseline Tier 3 Use Case C. - data from all data servers (WN and stand alone) Physical machine w/ local xrootd functionality Overlay xrootd functionality Public IP network Head node - Xrootd read-only redirector Xrootd read-only data server Outgoing read only data flow Information flow to global redirector

8. Xrootd usage at Duke Users begrudgingly are using Xrootd More senior folks like to use NFS like access Then to use xrootdfs to access the storage Graduate students much more adaptable.