Storage area Network(SANs)
Topics of presentation
What is Storage Area Network
Benefits of SAN Environment
SAN Components
Potential Storage Services Locations
Challenges of SAN Management
Ways to Manage a Storage Subsystem
WORLD WIDE NAMES
Simple Architecture of SAN
Redundant Architecture of SAN
Fibre channel vs. IP based technology
Summary of RAID levels
Storage services requirement
STORAGE AREA NETWORK
A dedicated network that interconnects hosts
and storage devices, usually via fibre channel
(FC) switches and optical fiber media. A storage
device is a disk sub system array with a set of
Local Area
disk drives.
Network
Fibre
Channel
Servers
Fibre Channel
Storage Area
Network
Benefits of SAN Environment
Storage Consolidation
Concurrent Access by Multiple Hosts
Use in Disaster Recovery Applications
Reduced Total Cost of Ownership
Reduction of management complexity/overhead
Improved availability
Scalability
Improved data protection
Increased capacity usage
SAN Components
FC cable
It is a high-speed data transmission technology used to connect multiple
hosts and storage devices over fiber-optic or copper cables.
SFP Module
Small Form-Factor Pluggable (SFP) modules are transceivers that interface
a motherboard with a FC cable and are used to covert electrical signals to
optical signals required for fibre channel transmission to and from devices
such as RAID controllers, switches and other fibre channel devices
Host bus adapters (HBAs)
It is also referred to as FC interface cards are installed into hosts. OS-specific
device drivers are usually installed for these adapters.
Storage devices
RAID architecture where all disks are independently addressed.
Interconnect devices such as fibre channel hubs or switches. Other specialpurpose devices are SAN gateways, bridges, routers, and extenders
Potential Storage Services Locations
Area of Intelligence
Hardware Platform
Host
• Servers
• Mainframes
Fabric
• Appliances
• Switches
• Directors
Subsystem
• Disks/RAIDs/Controllers
• Filers
• Tape Libraries
Challenges of SAN Management
A SAN must be managed at multiple points
Server OS
HBA
Switch
 Storage Array
Dependencies
The biggest challenge is understanding the dependencies of the various
elements upon each other.
Device drivers compatibility issues.
Problems
The new HBA has a different WWN than the old
one and so zoning information in the SAN.
Ways to Manage a Storage Subsystem
Out-of-Band Storage Subsystems
The controllers in the storage subsystem are managed directly
over the network through the Ethernet connection on each
controller in the storage subsystem.
In-Band Storage Subsystems
The controllers in the storage subsystem are managed through
an Ethernet connection on a host instead of using the Ethernet
connections on each controller
WORLD WIDE NAMES
It guarantees uniqueness within a large SAN fabric. There are two type of
WWNs:
Node WWNs—These are allocated to the entire adapter.
Port WWNs—These are assigned to each port within an adapter. These
are used for SAN zoning
Simple Architecture
LAN
Server
Server
HBA
HBA
Switch
Controller
Storage Array
Backup
Server
Tape Library
The Fibre Channel switch is an intelligent
device that collects information about the SAN
network topology and attached devices.
Switches Enable simultaneous communication
between multiple endpoints (such as a server and
storage disk)
Provide capabilities for managing those
connections between devices so that access is
controlled (through zoning)
Provide physical connectivity for failover and
load balancing
Redundant Architecture
Public LAN
Production servers
HBA
HBA
HBA
3
HBA
2
HBA
HBA
1
Backup server
switch
switch
redundant components—controllers,
switches, ports, HBAs
Cabling to ensure that there is no single
point of failure.
No cable connection between the two
switches.
ports
Controller
Controller
Switches remain independent.
Tape Library
Redundancy in various component
Redundancy can be on host level
Multiple HBA’s.
Redundancy can be on switch level
two or more switches.
Redundancy can be on storage
level ,connecting storage controller
with Expansion units.
Fibre channel vs. IP based technology
Servers
Fibre Channel
Cost and complexity
IP
Fabric devices Cost and complexity
Ethernet and TC/IP networking
technologies are familiar.
Fibre Channel networking
requires specialized expertise.
Ethernet networking components
are less expensive.
Fibre Channel networking
components are considerably more
expensive than IP.
One networking technology to
network clients, servers, and
storage.
Performance
4 GB Fibre Channel networking
components available today
Deterministic performance
Performance
Storage arrays
1 GB Ethernet networking
components available today
Not ideal for SAN solution
RAID levels
RAID 0 is the fastest and most efficient array type but offers no data
redundancy or fault-tolerance.
RAID 1 is the array technique of choice for performance-critical, faulttolerant environments and is the only choice for fault-tolerance if no more
than two drives are available.
RAID 3 is a popular choice for data-intensive or single-user applications that
access long sequential records. However, it does not typically allow multiple
I/O operations to be overlapped.
RAID 5 is generally the best choice for multi-user environments that are not
particularly sensitive to write performance. At least three, and typically five
or more drives are required to build a RAID 5 array.
Storage services requirement
Manageability
Capacity
Recoverability
Performance
Security
Availability
Storage services require scalability in
Size
number of nodes
Speed
throughput
Distance
Reach
SAN Environment in NUST DATACENTER
Hosts
IBM Xseries 346
2
Switch
Brocade ibm 2005-H16
1
Storage controller
Ibm Ds 4300
2
HBA
Qlogic 2340
2
XSeries 346
Qlogic 2340
Brocade ibm 2005-H16
Enterprise Management Window
The Enterprise Management Window (EMW)
provides high-level management of storage
system