INFSO-RI Enabling Grids for E-sciencE The gLite File Transfer Service: Middleware Lessons Learned form Service Challenges Paolo Badino On behalf of the JRA1 Data Management team CHEP06 - Mumbai, 14 February 2006

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 2 Outline The gLite File Transfer Service –in LCG Service Challenge 3 –Architecture –Administration –Security Result LCG Service Challenge 4

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 3 gLite File Transfer Service Low Level, point to point data movement service Part of the gLite Middleware Asynchronous transfers Based on Globus GridFTP, SRM Retry policies Not just a Reliable Transfer Service

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 4 LCG Service Challenges Production Quality Focus on Service: –Network service –Robust file transfer service –Sustainability Heterogeneous Environment –Castor2, dCache, DPM Service Challenge 2 –Radiant Service Challenge 3 –FTS (gLite 1.4.1) –CMS Phedex

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 5 The Key Concept: The Channel Logical unit of management –Represent a directed network pipe between two sites Mono-directional Independently manageable –State –Number of streams –Number of concurrent transfers Inter-VO scheduling –VO share No Routing

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 6 FTS Architecture FTS Web Service –User, Administration and Monitoring Interfaces File Transfer Queue File Transfer Agents –VO Agents –Channels Agents SOAP API and CLI

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 7 Transfer Jobs and Files Job –Represent the transfer request –Identified by a GUID File –source-destination file names pair Job States File States

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 8 Channel Administration Channel has a number of properties –State  Active  Inactive  Drain  Stopped  Halted –Number of concurrent files transfers –Number of streams –VO Share

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 9 Channel Agent Properties Transfer Type –SRM Get & Put + 3 rd party GridFTP –SRM Copy Timeouts –SRM interactions –Transfer –Transfer Markers TCP Buffer Size

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 10 Security: Roles Submitter User Administrator Vetoed User Channel Manager VO Manager Gridmap files VOMS roles

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 11 Security: Delegation Delegated User Credentials retrieved from MyProxy Agents are Authorized Retrievers –Enough for Production –… problematic for Analysis Delegation PortType

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 12 Monitoring Provides statistic information based on the FTS behavior and usage –Snapshots of number of requests in a given state –Average rate and bytes written in a given period Grouped by VO or Channels Channel Monitoring

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 13 FTS Web Interface

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 14 Retry Logic Simple retry strategy –Retry all the files up to 3 times, independently of the error reason Complex retry strategy (gLite 1.5) –Evaluate the transfer attempts history –Resilient to failures in the error handling Experiments’ specific retry logic (gLite 1.5)

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 15 What SC achieved so far SC3 Rerun (January 2006) All sites achieved target rate 8/11 sites achieved nominal rate

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 16 Preparing for SC4 Stability Sustainability Robustness Monitoring Procedures SRM v2 Integration with experiments’ frameworks –Hooks/Catalog plug-ins

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 17 Summary gLite FTS –Reliable Transfer Service –Transfer Management Tool LCG Service Challenge 3 –Architecture  Channels –Security –Feedbacks from experiments –Results achieved FTS in LCG Service Challenge 4

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 18 Links gLite – gLite JRA1 Data Management – Service Challenges Wiki – FTS Wiki –

Enabling Grids for E-sciencE INFSO-RI The gLite File Transfer Service: Middleware Lessons Learned from the Service Challenges 19 SC3 CERN Setup Production Pilot