1. Storage Survey and Recent Acquisition at LAL Michel Jouvin LAL / IN2P3 jouvin@lal.in2p3.fr

2. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 Outline Context and requirements Options considered Solutions evaluated

3. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 Context SAN deployed and working very well –Dual redundant fabric (2 ports available on each) –1 Gb/s technology 1 consolidated main file server –Based on HP TruCluster technology (2 machines) –Tru64 Advfs allows for huge filesystems (1TB or +) –Distributed file system protocol : NFS (and CIFS) 1 storage array (Compaq ESA 12000) –1,5 TB : almost full –SCSI2 Disks difficult to find, expensive, low perfs

4. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 Need for more TBs Experiments want more data locally –D0 group requested 1 TB more in 2003 –Expect other groups in the near future (Auger, Planck, Babar) –Request for standard file system space To complement HSM/HPSS huge space available in main centers –Issue is space rather than performance (mainly sequential) Low budget : 45 K€ for 1,5 user TB (2 raw TB) –Disks, controllers, servers, switches…

5. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 Option 1 : Server based IDE RAID Advantage = cost –A good Linux server is not very expensive –Disks are cheap Drawbacks –Doesn’t scale : more TBs = more servers Can be nightmare to manage with NFS –No high availability (or not mature) –Don’t integrate with current SAN infrastructure

6. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 Option 2 : SAN based IDE RAID Advantages –SAN integration : easy to manage –Cost # 8€/GB Drawbacks –Generally not dual redundant controllers –Doesn’t scale : more TBs = more controllers Serial ATA allows 1 disk per bus (channel) Hidden cost : need for more FC ports –No TruCluster support : need to setup a new server Lack of high availability (Linux) Significant cost increase

7. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 Option 3 : SAN based SCSI RAID Advantages –SAN integration : easy to manage –More Scalable than IDE : ability to grow to 5TB –High availability : dual redundant controllers –TruCluster support : server consolidation Drawbacks –Cost Controllers : significantly higher than IDE RAID Disk relatively expensive : less and less manufacturers –Technology end of life ? Replaced by Serial ATA for low end, FC for high end

8. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 Option 4 : SAN based FC RAID Advantages –SAN integration : easy to manage –Scalability Ability to grow until 32TB or + Disk pools sharing between multiple OS –High availability : dual redundant controllers –FC Disk performance –TruCluster support : server consolidation Drawbacks –Cost Controllers > 50 K€ (public price…) Disks (143 GO) # 10€/GB (raw disk)

9. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 Selected Option : FC RAID Technically most attractive Large (huge) discount can be expected 3 vendors considered/accepted to compete –Requirement : 1,5TB for 45 K€ –Vendors selection based on technical leadership and ability to obtain specific conditions

10. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 HP EVA110 HP StorageWorks natural candidate –Long relationship –TruCluster server High end technology –Back end virtualization Raid level defined at LUN level Dynamic reconfiguration of pools and LUN Drawbacks –Management appliance (dedicated PC) required –Dedicated rack needed –High impact cost on small configuration

11. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 StorageTek (LSI) D178 Middle range controllers –Perfs probably a little bit lower than EVA Dynamic resizing of LUN and RAID groups Bladestore : disks are FC modules made of 5 ATA disks –Price/GB divided by 2 –Minimum configuration = 5TB (1 blade = 1TB) –Ability to mix FC disks and bladestores in the same config Support of TruCluster unclear

12. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 Hitachi HDS 9570V 4 FC loops (backend) in each disk shelf –Only 2 per shelf at competitors No dynamic resizing of RAID groups –Coming soon Support of TruCluster –Clean implementation of multipath access and fail over Efficient cache mirroring –Only writes are mirrored

13. 20/5/2003 LAL Storage Survey - HEPix - Amsterdam 2003 Option Selected : HDS 9570V At the end, the less expensive… –Next 2 TB cost ~ IDE2FC Better support of TruCluster (compared to STK) Most attractive feature of STK : bladestore –Not appropriate for « small » configuration Will be connected at 1Gb/s to start –Fabric upgrade next year if possible Very excited (anxious ???) to test cooperation between vendors in SAN environment…!!!