ASIS et le projet EU DataGrid (EDG)

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

2. Outline • ASIS reminder • EDG WP4 and software distribution • Comparison

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

4. Clients 3/03: 3710 ASIS at CERN: evolution … Clients 10/99: 1680

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

6. … and its impact on ASIS • ASIS cannot easily handle ‘foreign’ packages (packages not generated by ASIShappi) • More and more applications already bundled with Linux distros -> no need for generating them with ASIS • RH61: 510 packages provided via ASIS, RH73: 160 • ASIS is built around a shared file system between repository, configuration database and clients. • File system scalability issues • 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.

7. EDG WP4

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

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

10. Linux Base packages LXBATCH CC packages EDG/LCG m/ware lxbatch444 lxbatch445 lxbatch446 WP4 tools used for SW distribution (II) Central Configuration Database (CDB): • Common store for configuration information • …including what software packages to deploy from which repository on which nodes • Configuration information can be arranged in templates: • Possible to create template combinations/hierarchies to match service structures • Each template can be maintained (using a GUI) by a different person • Configuration information is validated and kept under version control using transactions

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

12. Mgmt API Mgmt API SUE/ NCM http ftp nfs afs Packages Repository B WP4 SW distribution architecture inventory Repository A CDB CLI packages config (RPM, PKG) GUI Client nodes SPMA.cfg cache SPMA

13. Comparison

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

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

16. Comparison: Package generation Package generation: • ASIShappi can build applications for any UN*X platform. • Application building is not addressed by WP4. • EDG uses the standard RPM build mechanisms • No equivalent build mechanism available for Solaris

17. Status and Documentation • > 700 nodes using SPMA at CERN (LXPLUS and LXBATCH) • To become >1000 before the end of the summer • Software Repository: HTTP based server clustering solution • Load balanced using DNS round robin • Replication done using rsync • Two platforms: RH73 and RH Enterprise Server 2.1 • WP4 home page: • http://cern.ch/hep-proj-grid-fabric • WP4 installation task: • http://cern.ch/wp4-install