1. October,18-22 2004 Scientific Linux experience @ INFN/Trieste B.Gobbo – Compass R.Gomezel - T.Macorini - L.Strizzolo INFN - Trieste

2. October,18-22 2004 2 Outline of Presentation Introduction Introduction Evaluation phase Evaluation phase SL Test installation SL Test installation Installation Installation Configuration Configuration Management Management SL and Compass Computing FARM SL and Compass Computing FARM

3. October,18-22 2004 3 Before moving to SL When the end of official support from RedHat was announced in 2003 we had all PCs running Linux RedHat 7.3 and 9 When the end of official support from RedHat was announced in 2003 we had all PCs running Linux RedHat 7.3 and 9 HEP community was evaluating different roads to follow HEP community was evaluating different roads to follow Initially we are waiting for a common answer coming from INFN Computing Committee and looking at what was moving around Initially we are waiting for a common answer coming from INFN Computing Committee and looking at what was moving around At our site we tried different distribution based on RedHat Enterprise Linux like At our site we tried different distribution based on RedHat Enterprise Linux like CentOS 3.1 CentOS 3.1 Fermi Linux Fermi Linux Scientific Linux 3.0.1 Scientific Linux 3.0.1

4. October,18-22 2004 4 Evaluation of the needs As time went by we decided to have a meeting in order to discuss how to meet the needs of people involved in different experiments As time went by we decided to have a meeting in order to discuss how to meet the needs of people involved in different experiments It was clear that there were many distributions which were a rebuild of RHEL3 from Red Hat’s source RPM stripped of parts that cannot be distributed without a license It was clear that there were many distributions which were a rebuild of RHEL3 from Red Hat’s source RPM stripped of parts that cannot be distributed without a license Need to have a distribution well maintained and validated by the HEP community Need to have a distribution well maintained and validated by the HEP community

5. October,18-22 2004 5 Scientific Linux – Final Test installation As Scientific Linux 3.0.1 was available we installed it on a few PC clients in order to test how user’s feeling was As Scientific Linux 3.0.1 was available we installed it on a few PC clients in order to test how user’s feeling was we got a good feedback we got a good feedback So we went on with the installation of SL 3.0.2 So we went on with the installation of SL 3.0.2 At the time SL 3.0.3 was released we had in production At the time SL 3.0.3 was released we had in production 10 PC client (desktop functionality) 10 PC client (desktop functionality) 1 PC with server functionality 1 PC with server functionality

6. October,18-22 2004 6 Scientific Linux – Final test installation No problems or complaints coming from users running their applications and software No problems or complaints coming from users running their applications and software Then the decision to upgrade all PCs running SL to the new SL 3.0.3 and to move more PCs to the new release Then the decision to upgrade all PCs running SL to the new SL 3.0.3 and to move more PCs to the new release Right now we have 30 PCs clients and 3 PCs servers with SL 3.0.3 installed Right now we have 30 PCs clients and 3 PCs servers with SL 3.0.3 installed

7. October,18-22 2004 7 Scientific Linux - Installation Kickstart is used to install SL on the PCs Kickstart is used to install SL on the PCs Kickstart file generated using Kickstart file generated using buildks which is a tool developed at INFN Trieste Buildks allows to install and configure linux PCs automatically based on group-specific policy a specific network group configuration Type of PC: multiboot or singleboot...

8. October,18-22 2004 8 Scientific Linux - Management Installed machines are currently managed via Linux-update, a tool developed locally Installed machines are currently managed via Linux-update, a tool developed locally Linux-update allows us to modify in a centralized way Linux-update allows us to modify in a centralized way Configuration files Configuration files Specific installations Specific installations RPM packets management RPM packets management Anyway YUM is easier and more powerful to manage RPM packets Anyway YUM is easier and more powerful to manage RPM packets

9. October,18-22 2004 9 Scientific Linux – Configuration (1/2) A local repository has been created for the SL 3.0.3 distribution A local repository has been created for the SL 3.0.3 distribution Every night via lftp a mirror is created copying the distribution from ftp://ftp.scientific.linux.org/linux/scientific/30 3/i386/ Every night via lftp a mirror is created copying the distribution from ftp://ftp.scientific.linux.org/linux/scientific/30 3/i386/ ftp://ftp.scientific.linux.org/linux/scientific/30 3/i386/ ftp://ftp.scientific.linux.org/linux/scientific/30 3/i386/ This distribution is locally accessible using ftp anonymous just open to the local network nodes This distribution is locally accessible using ftp anonymous just open to the local network nodes

10. October,18-22 2004 10 Scientific Linux – Configuration (2/2) Linux PCs are configured as “YUM clients” of the local FTP server hosting the distribution Linux PCs are configured as “YUM clients” of the local FTP server hosting the distribution Update is done as the PC starts up and via a cron job using the simple command yum update as running Update is done as the PC starts up and via a cron job using the simple command yum update as running Kernel update is not managed by an automatic tool Kernel update is not managed by an automatic tool After a test phase it is installed manually After a test phase it is installed manually

11. October,18-22 2004 11 Scientific Linux – Release upgrade Moving from SL 3.0.2 to 3.0.3 was smooth and painless Moving from SL 3.0.2 to 3.0.3 was smooth and painless A script was created and run on all PCs with SL 3.0.2 installed A script was created and run on all PCs with SL 3.0.2 installed They were updated to the new release using mainly yum update and just a few more things as running They were updated to the new release using mainly yum update and just a few more things as running At the end just a reboot was necessary (for the new kernel) At the end just a reboot was necessary (for the new kernel)

12. October,18-22 2004 12 ACID (The COMPASS Trieste Compute Farm) Current Environment Current Environment Hardware Hardware 32 PC clients, 4 disk servers, 1 tape server + a small tape library (STK L40), 1 Oracle server, 1 supervisor and software repository server. All two processors machines 32 PC clients, 4 disk servers, 1 tape server + a small tape library (STK L40), 1 Oracle server, 1 supervisor and software repository server. All two processors machines Software: Software: OS: Red Hat Linux 7.3 (but Oracle server: it runs Red Hat AS2.1) OS: Red Hat Linux 7.3 (but Oracle server: it runs Red Hat AS2.1) Just few packages patched for local deeds: Just few packages patched for local deeds: kernel (NFS over TCP, 32k R/W size, F.Collin patches to Tape Drivers), OpenAFS, OpenSSH (local setup), CASTOR (it is a CERN software, small changes in code, local setup) kernel (NFS over TCP, 32k R/W size, F.Collin patches to Tape Drivers), OpenAFS, OpenSSH (local setup), CASTOR (it is a CERN software, small changes in code, local setup) B. Gobbo

13. October,18-22 2004 13 ACID (The COMPASS Trieste Compute Farm) Software Software Monitoring: BigBrother 1.9e (Quest Software) Monitoring: BigBrother 1.9e (Quest Software) Resource Management: Grid Engine 5.3 (Sun Open Source Software) Resource Management: Grid Engine 5.3 (Sun Open Source Software) HSM: CASTOR 1.7.1.5 (CERN Software) HSM: CASTOR 1.7.1.5 (CERN Software) RPMs upgrade using LinuxUpdate tool (Developed in INFN Trieste) RPMs upgrade using LinuxUpdate tool (Developed in INFN Trieste) B. Gobbo

14. October,18-22 2004 14 ACID (cont.d) Upgrades to be done before end of the year Upgrades to be done before end of the year Hardware Hardware ~6 more PC client nodes (with Opteron?) ~6 more PC client nodes (with Opteron?) Software Software OS: Move to Scientific Linux (CERN Version under test) OS: Move to Scientific Linux (CERN Version under test) 2 Client nodes already migrated for tests 2 Client nodes already migrated for tests 1 Server installed with Red Hat EL3 1 Server installed with Red Hat EL3 All needed software already ported All needed software already ported Experiment software porting basically finished. Experiment software porting basically finished. Initially we had problems with Grid Engine 6.0: AFS token is not exported (that is a major problem as user home directories are under AFS). Lack of support for AFS credential in qsub. Anyhow Grid Engine 6.0 now works. Initially we had problems with Grid Engine 6.0: AFS token is not exported (that is a major problem as user home directories are under AFS). Lack of support for AFS credential in qsub. Anyhow Grid Engine 6.0 now works. B. Gobbo

15. October,18-22 2004 15 ACID (cont.d) Software Software Few changes are needed to “adapt” distribution to local environment Few changes are needed to “adapt” distribution to local environment Mainly remove some “too-CERN-related” items Mainly remove some “too-CERN-related” items We keep CERN built kernel We keep CERN built kernel We are still considering “pure” SL too, as an alternative We are still considering “pure” SL too, as an alternative In that case few packages need to be added. Kernel has to be rebuilt. In that case few packages need to be added. Kernel has to be rebuilt. We keep local mirror of SLC and SL repository We keep local mirror of SLC and SL repository Following the CERN model: upgrade via APT (from the local repository) Following the CERN model: upgrade via APT (from the local repository) We had a look at QUATTOR too We had a look at QUATTOR too But the farm is not so big. Probably such a powerful too is not needed But the farm is not so big. Probably such a powerful too is not needed B. Gobbo