CASPUR SAN News Andrei Maslennikov Orsay, April 2001

A.Maslennikov - Orsay Will be discussed: Goals Fabric Bridges Adding a new device to fabric Our devices Distributed Tapes Some plans

A.Maslennikov - Orsay Goals Distributed Tape Drives - Modern tape drives are rather expensive - To get a good ROI drives should be shared at no loss of performance Stay along with technology that has future - Speeds will grow to 200 MB/sec and to 400 MB/sec - Switches will become interconnectable over WAN with ATM/STM Inteworking Units Ability to relocate devices et ease - Fibre Channel SAN allows for congestion-free, high-speed connectivity with guaranteed delivery - Since a device is attached to SAN, it may preserve it’s physical location - Devices may be remotely reassigned from one host to another - NB: we only want this for our very central and institutional services

A.Maslennikov - Orsay Fabric - We use Brocade switches 2400 and Currently 2x2400 and 2x2800, 48 ports in total - Brocade Switch: o supports practically all FC COSes and peripherals o performant: up to 233 MB/sec o runs a user-friendly Fabric OS and graphical interface o whole SAN can be administered from any switch o allows for zoning o allows for redundant path o duffused to such extent that device vendors consider Brocade connectivity a must - Only dim point - OS upgrades o Switch reboot is required o Way out: spare ports on other switches and scheduled shutdowns o But this is true for any make of switch….

A.Maslennikov - Orsay Brocade zone 1 Brocade zone 2 HBAs Host 1 Host 2 Tape Disk1 Disk2 Host-Based Adapters - We tried Emulex Light Pulse 8000 and Qlogic QLA Both models are fully supported on Solaris, AIX, Linux, Wxx - We however have discarded QLA2200 at the initial stage, as we observed inteferences between two Solaris hosts connected to the fabric with this HBA and sharing a tape drive: In this case, a job on host 1 was running a heavy test I/O job on disk 1. And reboot of host 2 resulted in a SCSI timeout error on host 1/disk 1. - In case of LP8000, this inteference was not seen. So we “jumped the Emulex train” and use them since on all our hosts. We will also be trying QLA2200 again soon, as their driver was long corrected.

A.Maslennikov - Orsay Bridges - We use 2 Crossroads StorageRouters 4200 to connect SCSI STK 9840 and DLT7000 tape drives to the fabric Features: o supports 2 SCSI buses (diff or single-ended) with up to 15 devices on each o GBIC slot o automatic configuration - Problem observed: o We were able to smoothly share DLT over Crossroads box 1 between 6 hosts o 9840 on Crossroads box 2 was shareable up to 3 hosts. Adding host 4 meant to jeopardize access to tape on all 4 machines… (tape off-line). o Crossroads was blaming Emulex and vice versa o Solution: two boxes had different firmware. Older firmware worked, newer -not

A.Maslennikov - Orsay New device, step-by-step - Make sure the fabric login occured - Find out the device WWNN / WWPN - Create a device alias (nickname) - Create/modify zones normally create one new zone for each HBA (give it an alias!) populate each zone with one HBA and disk and tape aliases do not put a disk device into two different zones, unless you know what you are doing no limitations for tapes - share them! - Set up the persistent bindings in the HBA driver configuration file - Create new devices (vary with OS)

A.Maslennikov - Orsay Our current devices Hosts - 5 IBM AIX ML8 (native and IBM-modified LP8000s) - 6 Solaris 7+/8+ (native LP8000s) Tapes - 1 STK DLT 7000 via Crossroads - 4 LTO on native FC - All tapes are shared Disks - 3 Artecon Lynx II arrays (single ctl) - 2 DotHill 4200 arrays (dual AA) - via 2 Gadzoox Bitstrip TW Hubs - 1 DotHill 7100 (dual AA) - 1 IBM 2102 (2 ctl) - Around 4 TB in total

A.Maslennikov - Orsay FC Library Tape Mounter Tape Dispatcher Distributed Tapes 9740 STK Library 9740 Mount comands via serial line 3584 mount commands via FC S A N hosts LTOs Mount request / Free tape via LAN 9840 DLT 4200 bridge scsi (1) Mount request > (2) Lock wait < (3) Mount command < (4) Mount rc (5) Access Tape (6) Free Tape >

A.Maslennikov - Orsay Some plans - Bring tapes to Linux DB hosts (backup) try both LP8000 and QLA2200 on RedHat - Try small (logical) slices of RAID-5 and RAID-0 non-shared scratch areas faster cache areas for AFS on front-end hosts (AIX and Tru64) system disks? - GPFS tests on SP3 with 4 DotHill 7200 systems on 4 nodes

A.Maslennikov - Orsay Projects for year 2001 Control and Monitoring - agent up and running on all Linux hosts - being ported to other architectures (encryption) - server integration with Syscontrol DB (event logs and configuration) Syscontrol DB - mysql now, migration to InterBase by the end of Hosts’ DB and Syslog event collector DB - Hooks for syscontrol applications Problem management - currently study possible solutions, Razor is one of the options Console Server - planned for the second half of currently look at the serial hardware Security - accent on host-based - host security “index” is being developed to integrate with Syscontrol