Phenix updated installation and configuration status - 2nd March 2007

• Minutes of the phone call held the 2nd March 2007
• Participants:
  • Sergio Maffioletti
  • Alessandro Usai
  • Tom Guptil
  • Derek Feichtinger
  • Sigve Haug

Status of installation and configuration

• WN (X2200)
  • SLC4.4 [tobe finalized and integrated into cfengine]

• CE (X4200)
  • 1 X4200 used for PNFS + postgres [ok]

• WN (X2200) * 1 X2200 used as dcache admin node (SRM + dcache packages) [ok]

• Thumper
  • 1 Thumper integrated as pool node [ok]
  • Configuration of pools
    • 1 pool write only and 1 pool read only per VO

• Problem encoutered, solutions and workarounds
  • se02 is not registering properly with dcache admin nodes: pools are seen as non active
  • Derek will test dcache installation procedure from scratch on se02
  • MonAMI monitor may not be usable as it is querying tables removed from latest dcache release
  • The final system will need some ad-hoc scripts/cron jobs for the update of CA list and grid-mapfiles

• Tests (tentative dates)
  • Reliability tests on whole system (Derek + Tom + Alessandro) --> 5 - 9 MArch
  • Performance test from WNs to Thumpers via dcache (Derek + Sigve + Alessandro) --> 2 - 9 March
  • Test different configurations of ZSF [ok]

• Organisation of the dCache tests
  • functionality tests
  • VO codes
  • local load tests (mainly dcap):
  • writing files in parallel from multiple nodes
  • reading same file from multiple nodes
  • trying to write file that is being written by another process
  • erasing file that is being read by another process
  • measure I/O rates as function of parallel clients
  • WAN protocol tests (SRM, gridftp)
  • CMS PhEDEx transfers
  • Storage access profile of CMS jobs -> they will use dcap protocol
  • Storage access profile of Atlas jobs -> for those using ARC, maily the access is through SRM and/or Gridftp
  • each VO should prepare their own specific tests
  • General test suite ( local and wan test ) will be prepared by Derek
  • Sigve will forward the test description to the Atlas contact to check if Atlas will need additional tests

SE dcache open issues

• • is it necessary to mount PNFS on Thumper ? yes if Thumper is running Gridftp ( thanks to Lionel Schwarz )
  • what is necessary for WN to use the dcap protocol to access the dcache pools ? WNs will point todcache admin node and it will redirect to the right Thumper

What bandwidth can we expect:

• We may have preformance problem from Dalco WNs to Thumper due to single Gb link from switch to switch
• Tom will check if both switches can be trunked together
• This is an important issue to keep in mind when planning the extention

Deadlines

• next week --> tests
• 15th March --> production

AOB

• update UI machine
  • 5 - 9 March reinstall UI
  • announce half day downtime

• VOBoxes --> Atlas VO could be moved to Xen node

• responsibility for Twiki areas (CSCS will take care)
  • Create 1 page per VO
  • add a page with logs of problems
  • VOBoxes page with info about how to start services
  • There will be one page per service/server involved

• We will produce a list of things to be checked before entering production
  • what needs to be available at cscs
  • What configurations needs to be modified at Tier-1 level
  • For every VO there will be a list of configurations to check

• We need to prepare a message for all users about the scheduled entering production

Resume of the Configuration

• 1 X2200 = cluster management system
• 1 X2200 = SRM + dcache domains + LCG SE related software
• 1 X4200 = PNFS + posgres
• 1 X4500 Thumpers = Gridftpd + dcache pool node
• 1 X4500 Thumpers = Gridftpd + dcache pool node

• ZFS configuration (Proposal):
  • 1 Thumper test with 4 Raid and 2 parity disks = 16TB + 4 spare disks
  • 1 Thumper test with 4 Raid and 1 parity disk = 18TB + 4 spare disks

• 1 ZFS pool per Thumper

• 1 Filesystem per VO per Thumper
• each VO gets space on both Thumpers

• Thumper dcache configuration
  • each Thumper will have 1 dcache pool per VO/FS (CMS,Atlas,dteam)
  • 1 Thumper will also have FS for lhcb and hone

-- SergioMaffioletti - 2 March 2007