ASIS et le projet EU DataGrid (EDG) Germán Cancio IT/FIO

German Cancio IT/FIO - n° 2 EPFL visit, 14/7/03 Outline u ASIS reminder u EDG WP4 and software distribution u Comparison

German Cancio IT/FIO - n° 3 EPFL visit, 14/7/03 ASIS: reminder u ASIS: stands for ‘Application Software Installation Service’ n Started 1993; joint project between CERN/IT and EPF Lausanne u Package generation: n assisted multiplatform application compilation (HAPPI) u Repository management: n Adding/removing/upgrading packages (HAPPI, ASIStm) n Repository replication (ASISlcm) u Client access (over shared file system) n Configurable agent (ASISwsm/p) u Repository contents at CERN: n CERNLIB, CASTOR, Compilers, GNU tools, LaTeX, editors… u Focus on providing an uniform application layer on multiple UN*X platforms

German Cancio IT/FIO - n° 4 EPFL visit, 14/7/03 ASIS at CERN: evolution … Clients 10/99: 1680 Clients 3/03: 3710

German Cancio IT/FIO - n° 5 EPFL visit, 14/7/03 … today’s changed environment… Since ASIS was designed… u RISC phaseout: n Only 2 CERN-IT supported Un*x OS (Linux & Solaris) u Large scale farms (LXBATCH scaling up to O(10K)) u Mature and reliable vendor package managers n RPM (RH Linux), PKG (Solaris) u Large number of default packages shipped with OS distros n RH73: ~ 700 packages, Solaris 8: ~ 410 packages u Availability of large local disks n Packages don’t have to be ‘links only’ to application servers

German Cancio IT/FIO - n° 6 EPFL visit, 14/7/03 … and its impact on ASIS u ASIS cannot easily handle ‘foreign’ packages (packages not generated by ASIShappi) n More and more applications already bundled with Linux distros -> no need for generating them with ASIS n RH61: 510 packages provided via ASIS, RH73: 160 u ASIS is built around a shared file system between repository, configuration database and clients. n File system scalability issues u Inside the ASIS project, the decision taken was to minimize further development efforts, and to participate in the design of the EDG fabric management work package.

German Cancio IT/FIO - n° 7 EPFL visit, 14/7/03 EDG WP4

German Cancio IT/FIO - n° 8 EPFL visit, 14/7/03 EDG WP4 u WP4 is the ‘fabric management’ work package of the EU DataGrid project. u Objective: n To develop system management tools for enabling the deployment of very large computing fabrics […] with reduced sysadmin and operation costs. u Includes solutions for n automated from scratch node installation n node configuration/reconfiguration n software storage, distribution and installation n storing, maintaining and retrieving configuration information.

German Cancio IT/FIO - n° 9 EPFL visit, 14/7/03 WP4 tools used for SW distribution (I) SWRep (Software Repository): u Client-server toolsuite for the management of software packages u Universal repository: n Extendable to multiple platforms and package formats (RHLinux/RPM, Solaris/PKG,… others like Debian dpkg) n Multiple package versions/releases u Management (“product maintainers”) interface: n ACL based mechanism to grant/deny modification rights n Current implementation using SSH u Client access: via standard protocols n HTTP (scalability), but also AFS/NFS, FTP u Replication: using standard tools (eg. rsync)

German Cancio IT/FIO - n° 10 EPFL visit, 14/7/03 WP4 tools used for SW distribution (II) Central Configuration Database (CDB): u Common store for configuration information n …including what software packages to deploy from which repository on which nodes u Configuration information can be arranged in templates: LXBATCHlxbatch444 Linux Base packages CC packages u Possible to create template combinations/hierarchies to match service structures u Each template can be maintained (using a GUI) by a different person u Configuration information is validated and kept under version control using transactions EDG/LCG m/ware lxbatch445lxbatch446

German Cancio IT/FIO - n° 11 EPFL visit, 14/7/03 WP4 tools used for SW distribution (III) Software Package Management Agent (SPMA): u Runs on every target node u Configurable locally or via CDB u Multiple repositories can be accessed (eg. division/experiment specific) u Plug-in framework allows for portability n System packager specific transactional interface (RPMT, PKGT) u Can manage either all or a subset of packages on the nodes n Useful for add-on installations, and also for desktops n Configurable policies (partial or full control, mandatory and unwanted packages, conflict resolution…) u Addresses scalability n Packages can be stored ahead in a local cache, avoiding peak loads on software repository servers (simultaneous upgrades of large farms)

German Cancio IT/FIO - n° 12 EPFL visit, 14/7/03 WP4 SW distribution architecture Packages Mgmt API Repository A packages Mgmt API CDB config Client nodes SUE/ NCM SPMA.cfg SPMA (RPM, PKG) GUI CLI cache Repository B inventory http afs nfs ftp

German Cancio IT/FIO - n° 13 EPFL visit, 14/7/03 Comparison

German Cancio IT/FIO - n° 14 EPFL visit, 14/7/03 Comparison: Software Repository Management access: u Both ASIStm and WP4’s SWRep provide authentication, and authorization mechanisms (using ACL’s) Client access: u ASIS: shared file system required. u WP4: Can be any of HTTP, NFS, AFS, FTP Replication: u The ASIS replication tool (ASISlcm) replicates both the repository contents and the default configuration. u WP4 does not require a specific tool for repository replication: standard tools (eg. rsync) already exist.

German Cancio IT/FIO - n° 15 EPFL visit, 14/7/03 Comparison: Software update client u SPMA can do everything ASISwsm(p) can do n Almost same design team… u SPMA can do more: n Manage all packages (system and applications) n Designed to use the system packagers (RPM, PKG) n Multiple repository access protocols n Cache management u Configuration: n In ASIS, only one default configuration profile n WP4 CDB: any number of profiles, version control u Configuration GUI: n ASIS provides a end-user GUI (tkwsm) n The WP4 CDB GUI (PanGUIn) is targeted towards sysadmins, but end-user GUI feasible

German Cancio IT/FIO - n° 16 EPFL visit, 14/7/03 Comparison: Package generation Package generation: u ASIShappi can build applications for any UN*X platform. u Application building is not addressed by WP4. n EDG uses the standard RPM build mechanisms n No equivalent build mechanism available for Solaris

German Cancio IT/FIO - n° 17 EPFL visit, 14/7/03 Status and Documentation u > 700 nodes using SPMA at CERN (LXPLUS and LXBATCH) n To become >1000 before the end of the summer u Software Repository: HTTP based server clustering solution n Load balanced using DNS round robin n Replication done using rsync u Two platforms: RH73 and RH Enterprise Server 2.1 u WP4 home page: n u WP4 installation task: n