Overview of the EMC CLARiiON Model

FC4500 Array

and Access Logix Overview

Departmental storage requirements Overview of CLARiiON features New issues with shared storage Solution using FC4500, host software and switches Configurations & Performance Summary Q&A

Departmental Storage Requirements

• Many departmental servers each requiring storage?
  • Most storage is direct attached or internal
  • Not flexible
  • Difficult to manage
  • Storage is seldom attached to the server that really requires additional capacity
• Clusters
  • Require external shared storage
  • Each node must have access to LUNs used for the cluster

   

EMC CLARiiON Architecture

Two Main Building Blocks DPE (Disk Processor Enclosure)
DAE (Disk Array Enclosure)

EMC CLARiiON Family

Constant Data Access - High Availability Features

Enclosure Architecture

Rear View of DPE

Rear View of DAE

DPE and DAE Disk Modules

• Dual-ported Fibre Channel disks
• Drive format - 520 bytes per sector
  • storage data - 512 bytes per sector
  • License Internal Code (LIC) or FLARE data - 8 bytes per sector
• FC-SCA-2 connector
  • Pin out defined by SFF-8045/8067 an industry standard
• Molded plastic carrier
• Spindle spin-up sequence per SFF-8045 an industry standard
  • Not all drives "spin-up" at the same time
    • "Spin-up" times can be changed
• System - Used by Licensed Internal Code (LIC) only
  • Buffering cache, LIC database; no host data! Amount can vary depending on version of LIC and SP
    • FC5500: 10 MB
    • FC5700: 14 MB
    • FC5300: 14 MB
    • FC4500: 20 MB
• Read, Write - Used for host data
  • Non-mirrored, no cache-like controls (more like"buffering")

   

Cache Settings

• End-Users enable or disable:
  • SP caching - All LUNs assigned to the SP can only use cache as enable on the SP
  • LUN caching - The LUN uses caching for reads or writes
  • Read and write caching - configured manually
  • RAID-3 write buffering - for all RAID-3 LUNs in the entire array
• Cache memory is allocated in pages, not bytes
  • Minimum number of bytes set aside
  • Page is dedicated to one I/O
  • Default size is 8k (2, 4, 8 and 16k possible)
  • Same size for all cache and both SPs

Components Required for Write Cache

• Two storage processors
• Two LCCs in the DPE
• Two power supplies in the DPE
• Cache vault disks (DPE disks 0-8) present
  • FC5300 uses iDAE disks 0-4
• One Standby Power Supplies (SPS)

Review of CLARiiON solutions prior to FC4500

• LUN partitioning
• FC-AL either direct or hub connection
• Only support "like" hosts per SP connection
• Entire physical array and its data are accessible to all hosts connected
• Any host with agent running and connected to an array can manage it

RAID Groups a.k.a. LUN Partitioning or Sub-LUNs

Four-Disk RAID-5 Group with Three LUNs

What are the potential issues?

• Windows NT will see all LUNs and attempt to take ownership
• The SUN system administrator could mount the NT LUNs
• A LIP will be disruptive to all hosts - normal feature with AL
• Shared bandwidth (100Mb per sec / "n" hosts) will not scale
• Active host with a lower ALPA could unfairly consume resources

Introducing the CLARiiON FC4500

• Support of existing infrastructure for investment protection
  • Navisphere centralized management
  • Modular, scalable architecture
  • Ideal for departmental/decentralized server and storage consolidation
• Enhanced connectivity - secure storage sharing via Access Logix
  • First CLARiiON array to support multiple heterogeneous hosts
  • Heterogeneous connection for Windows NT, Windows 2000, Solaris and AIX
• Fourth generation full Fibre array
  • Best performing CLARiiON array to date!

   

Array Features

• Implemented in Core Software a.k.a. Licensed Internal Code, Flare or ucode
• Fair Access to Array Resources
• Security - Access Logix
  • Data Access
  • Management
• Storage Groups
• Failover with two independent switches using ATF

Access Logix Software

• Enables shared storage environment
  • Storage appears as direct-attached, dedicated storage
• Data protection and access control on Fibre Channel Enterprise Storage Networks
  • Utilizes switched Fibre Channel data paths
• Highest security available for storage networks
  • Array-based access controls
  • Multi-host performance management

   

FC4500 Access Logix

Fairness

• Fairness
  • Dynamic - self tuning
  • Balancing access to logical units (LUNs) to ensure that one host does not unfairly monopolize the resources of the physical storage system
  • Array resident component implements starvation avoidance
  • On/off switch to disable if heuristic worse for specific application

   

Storage Group

• Storage Group (aka LUN masking)
  • A subset of LUNs grouped for access by one or more hosts and inaccessible to other hosts
  • Initiator can be connected to 0 or 1 storage groups per array
• LUN mapping table
  • LUN Alias - Customer defined name
  • Flare LUN - LUN number created during binding
  • LUN data is not changed by creating or removing mapping table entries
  • Appears to the host as an entire array or SCSI target

   

Example: Designing Storage Groups

(In this example Host A will require access to LUNs 0-3 and Host B will require access to LUNs 1-4.)

Features Implemented on Hosts

• Navisphere Manager Configures
  • Access Logix
    • configuration access control password on array
    • data security
• Agent
  • Initiator registration at startup
• ATF
  • failover with two independent switches
  • "congestion avoidance" for array resources
• Fabric aware drivers

Turning on "Management Login"

• Enable "Configuration Access Control"
  • Need to specify password
  • No host can issue change commands anymore
• Enable access for selected hosts
  • Add an entry for the desired host using the password created above

   

Enabling Access Logix

• Enable Data Access Control
  • Hosts can now only see"their" LUNs once defined
  • Newly connected hosts see no LUNs at all
• Create Storage Groups as needed
  • Designate as shared/dedicated
  • Add LUNs to Storage Groups
  • Connect hosts to Storage Groups
• Modify Storage Groups

Sample FC-SW Configuration

Initiator Registration Records

• Initiator Registration Records - Initiator registration information stored permanently on the array
  • Each includes: sending HBA UID, receiving SP, initiator type, hostname, and other information
  • Used by the GUI to match HBAs from the same host
  • Used by the array
    • to present different initiator behavior to different hosts
    • to keep access control information
    • to determine if the system has management access
• This is how a single port can work in a heterogeneous environment!

Storage Tree View

Connectrix Departmental Switch Overview

• Model SW-08-RACK, workgroup has 8 ports
• Model SW-16-RACK, departmental has 16 ports
• Required licenses, GBICs and first optical cable are shipped in the package
• Managed via telnet or browser
• Zoning

FC-SW Configurations

• It allows up to 15 hosts to share up to four FC4500 arrays
  • Host/Array limitation is based upon 16 ports on the switch
  • Practical limitation based on host I/O requirements
  • NT 4.0 SP5/6 management station required
  • NT and Solaris 2.6, 2.7 are currently available
  • Win2K, IBM-AIX, HP/UX to be available this Q2/00
• Uses two Connectrix models 8-Port or 16-Port switches

New Features with May Release of the FC4500

• Support of HP/UX, IBM-AIX and Win2K
• WWN unique to Array in Fabric environments
  • Older version of Core software had WWN hard coded to SP
  • Made hot swap difficult in some environments
• RAID 3 Support
• Warm Reboot
  • Ability to upgrade Core Software without rebooting host
    • Requires ATF and current Core Software
  • not available for HP
• Support of the Connectrix DS 1032

HP/UX Attaches

• Now Supports >8 LUNs
• Homogeneous Support only on Array
• HP/UX does not yet support Fabric
• 8 and 16 port Switches in Quickloop Mode only

Upgrade Considerations

• HBAs, cables and Hubs will require replacement
• Supported HBAs
  • Emulex LP8000 - Minimum Firmware 3.x
  • JNI FC64 - Requires MIA
• Requires current versions of drivers, agents, ATF and Navisphere Manager Required!
• Data in place upgrade for FC5700 - upgrade for FC5500 soon to follow

Configuration Limitations

• Cascaded switches are not supported
• Long Wave GBICs not supported
• All switch connects are point-to-point (no public loop)
• Only Model FC4500 array is supported for connection to switches
• Colossus model C8872FG-A not supported
  • First generation FC disk does not support dual porting
• Access Logix required for FC-SW connection

CLARiiON's Full Fibre Storage Processor Progression

Summary

• Storage Area networks allow for easier centrally managed storage
• CLARiiON is part of the EMC ESN and scaleable
• ESN offers security protection for data access
• Multiple separate nodes can utilize the same array lowering the overall storage costs to the customer

Reference Material

• Sales Support Help Desk
• Documentation
  • 069-000882-02 Navisphere 4.X Manager Installation and Operation for Microsoft Windows NT Environments
  • 014-002901-00 CLARiiON Disk-Array Enclosure (DPE) Installation and Service
  • 014-002912-01 CLARiiON Disk-Array Storage Systems Configuration Planning for Fibre Channel Environments
• Training
  • C870 Storage Area Networks: Technical Concepts
  • C875 CLARiiON Shared Storage Implementation and Troubleshooting