understanding nas (network attached storage)
TRANSCRIPT
Section 3 – Networked StorageSection 3 – Networked Storage
Introduction
Section Objectives
Upon completion of this section, you will be able to:
Describe the elements, connectivity, and management of: Direct Attached Storage (DAS), Network Attached Storage (NAS), FC and IP Storage Area Networks (SAN), Content Addressed Storage (CAS)
Compare the benefits and challenges of each of the storage models
In this Section …
This section contains the following modules:
1. Direct Attached Storage (DAS)
2. Networked Attached Storage (NAS)
3. Storage Area Networks (SAN)
4. IP Storage Area Networks (IP SAN)
5. Content Addressed Storage (CAS)
Direct Attached Storage (DAS)Direct Attached Storage (DAS)
Module 3.1
Direct Attached Storage (DAS)
After completing this module you will be able to:
Discuss the benefits of DAS based storage strategy
Describe the elements of DAS
Describe the connectivity options for DAS
Discuss DAS management considerations
Identify the best environments for DAS solutions
DAS Benefits
Ideal for local data provisioning
Quick deployment for small environments
Simple to deploy in simple configurations
Reliability
Low capital expense
Low complexity
Physical Elements of DAS
CPU
Motherboard
Clustered group of processors
Processor cards
Complete system
Internal
External
Hard disk(s)
CD-ROM drive
Optical drive
Removable media
Tape devices/tape library
RAID/intelligent array(s)
Portable media drives
Connectivity
Storage
DAS Management: Internal
Host provides:– Disk partitioning (Volume management)
– File system layout
– Data addressing
Direct Attached Storage managed individually through the server and the OS
DAS Management: External
Array based management
Availability – multi-path I/O
Lower TCO for managing data and storage Infrastructure
DAS Performance Considerations
Factors to be considered for DAS performance:
• Hard disks
• Memory cache
• Virtual memory (paging)
• Storage controllers• Protocol supported (e.g. SCSI, FireWire, USB, etc.)
• RAID level
• Bus
Internal DAS Application Example
Hard Drive40 Pin Ribbon Cable
Motherboard
External DAS Application Example
ESCON HBACable for
external DAS connectivity
DAS Challenges
Hosts must be directly connected
Data availability issues–Many single points of failure
Bus, multiple path software, host, application
Data slowdowns possible–CPU congestion, caching, multi-pathing
Volumes are not globally available to all hosts
Scalability concerns
DAS Challenges
Hosts must be directly connected
Data availability
Data slowdowns possible– CPU congestion, caching, multi-pathing
Scalability is limited– Number of connectivity ports to hosts
– Number of addressable disks
– Distance limitations
Downtime required for maintenance
Module Summary
Key points covered in this module:
DAS can be:– An integrated part of the host computer
– Directly connected to a single server
DAS is made up of a CPU, connectivity, and storage devices – There are several options within each of these categories
DAS connectivity uses block-level access protocols
Check Your Knowledge
What are the physical elements of DAS?
Give an example of when DAS is a good solution.
Describe internal DAS connectivity.
Describe external DAS connectivity.
What are some areas that you need to consider as part of DAS management?
Network Attached Storage (NAS)Network Attached Storage (NAS)
Module 3.2
NAS – Network Attached Storage
After completing this module, you will be able to:
Discuss the benefits of NAS based storage strategy
Describe the elements of NAS
Discuss connectivity options for NAS
Discuss NAS management considerations by environment
Identify the best environments for NAS solutions
In this Module …
This module contains the following lessons:
What is NAS?
Managing a NAS Environment
NAS Application Examples
Lesson: What is NAS?
Upon completion of this lesson, you should be able to:
Define NAS and describe its key attributes
List the benefits of NAS
Describe NAS connectivity
NAS Evolution
Network Attached Storage (NAS)
Stand Alone PCNetworked File SharingNetworked PCsPortable Media
for File Sharing
What is NAS?
NAS is shared storage on a network infrastructure. Clients
ApplicationServer
PrintServer NAS Device
NAS Head Storage
General Purpose Servers vs. NAS Devices
Network
Operating System
I/O
File System
Print Drivers
Applications
General Purpose Server(NT or Unix Server)
Network
Operating System
File System
Single Function Device(NAS Server)
Why NAS?
Supports global information access
Improves efficiency
Provides flexibility
Centralizes storage
Simplifies management
Scalability
High availability – through native clustering
Provides security integration to environment (user authentication and authorization)
NAS Device Components
NAS Device
CIFSCIFSNFSNFS
Network InterfaceNetwork Interface
Storage InterfaceStorage Interface
NAS Device OSNAS Device OS
SCSI, FC, or ATA
IP Network
NAS File Services Protocols: NFS and CIFS
NAS Device
Network InterfaceNetwork Interface
Storage InterfaceStorage Interface
NAS Device OSNAS Device OS
SCSI, FC, or ATA
CIFSCIFSNFSNFSIP Network
Windows
Unix
NFS
CIFS
Network File System (NFS)
Client/server application
Uses RPC mechanisms over TCP protocol
Mount points grant access to remote hierarchical file structures for local file system structures
Access to the mount can be controlled by permissions
Common Internet File System (CIFS)
Public version of the Server Message Block (SMB) protocol
Client applications access files on a computer running server applications that accept the SMB protocol
Better control of files than FTP
Potentially better access than Web browsers and HTTP
NAS Physical Elements
Data movers/filers
Management interface– Configure network interfaces
– Create, mount, or export file system
– Install, configure and manage all data movers/filers
– Can be accessed locally or remotely
Connectivity – NAS head to storage
– NAS head to network
Storage
Integrated vs. Gateway NAS
Integrated NAS
NAS Gateway
IP Network
IP NetworkFC Fabric
NAS Head
NAS Head
Integrated NAS System
Integrated NAS System
NAS HeadStorage
Direct AttachIP Network
Gateway NAS System
Clients
Application Servers
Storage
NAS Gateway
FC Switch
IP Network
Lesson Summary
A NAS server is an appliance optimized for file serving functions.
Generally it has a specialized operating system
NAS supports multiple protocols
NAS can be implemented as an integrated system or as a gateway
Fibre Channel Storage Area Networks (SAN)Fibre Channel Storage Area Networks (SAN)
Module 3.3
Fibre Channel Storage Area Networks (SAN)
Upon completion of this module, you will be able to:
Describe the features and benefits of SAN.
Describe the physical and logical elements of SAN.
List common SAN topologies.
Compare and contrast connectivity devices.
Describe connectivity options of SAN.
Describe the I/O flow in the SAN environment.
List SAN management considerations.
Describe applications of a SAN strategy.
In this module …
This module contains the following lessons:
Fibre Channel SAN Overview.
The Components of a SAN.
FC SAN Connectivity.
SAN Management.
SAN Deployment Examples.
Case Study and Applications of FC SAN.
Lesson: Fibre Channel SAN Overview
Upon completion of this lesson, you will be able to:
Define a FC SAN.
Describe the features of FC SAN based storage.
Describe the benefits of an FC SAN based storage strategy.
Business Needs and Technology Challenges
Information when and where the business user needs it
Integrate technology infrastructure with business processes
Flexible, resilient architecture
What is a SAN?
Dedicated storage network
Organized connections among:
Storage
Communication devices
Systems
Secure
Robust.
Evolution of Fibre Channel SAN
SAN IslandsFC
Arbitrated Loop
InterconnectedSANs
FCSwitched Fabric
Enterprise SANs FC Switched Fabric
HUB
Benefits of a SAN
High bandwidth – Fibre Channel
SCSI extension– Block I/O
Resource Consolidation – Centralized storage and management
Scalability– Up to 16 million devices
Secure Access– Isolation and filtering
Lesson Summary
Topics in this lesson included:
Definition of a SAN
Features and Benefits of SANs
Lesson: The Components of a SAN
Upon completion of this lesson, you will be able to:
Describe the elements of a SAN.– Host Bus Adapter (HBA)
– Fiber Cabling
– Fibre Channel Switch /Hub
– Storage Array
– Management System
Components of a Storage Area Network
Host Bus Adapter (HBA)
Fiber Cabling
Fibre Channel Switch /Hub
Storage Array
Management System
HBAHBA
SAN-attached Server
SAN
Nodes, Ports, & Links
Node
HBA
Port 0Port 0
Port 1Port 1
Port nPort n
Link
Port 0Port 0Rx
Tx
HBA
Host Bus Adapters
HBAs perform low-level interface functions automatically to minimize the impact on host processor performance
HBA
Connectivity
Single Mode Fiber
Storage
Multimode Fiber
Host
Connectivity Devices
Basis for SAN communication– Hubs, Switches and Directors
HBA
Storage Resources
Extension of the basic disk drive to an array.– Provides storage consolidation and
centralization
Features of an array– High Availability/Redundancy
– Performance
– Business Continuity
– Multiple host connect
HBA
SAN Management Software
A suite of tools for managing SAN including access of host to storage arrays.
Provides integrated management of SAN environment.
Web based GUI or CLI
Lesson: Summary
Topics in this lesson included:
The elements of a SAN:– Host Bus Adapter (HBA)
– Fiber Cabling
– Fibre Channel Switch /Hub
– Storage Array
– Management System
Lesson: Fibre Channel SAN Connectivity
Upon completion of this lesson, you will be able to:
Describe the Fibre Channel SAN connectivity method and topologies
Describe Fibre Channel devices
Describe Fibre Channel communication protocols
Describe Fibre Channel login procedures
Fibre Channel SAN Connectivity
Core networking principles applied to storage
Servers are attached to 2 distinct networks– Back-end
– Front-end
Users &Application
Clients
Storage & Application
Data
Servers & Applications
SANswitchesdirectors
IPnetwork
What is Fibre Channel?
SAN Transport Protocol– Integrated set of standards (ANSI)
– Encapsulates SCSI
A High Speed Serial Interface– Allows SCSI commands to be transferred over a storage network.
Standard allows for multiple protocols over a single interface.
World Wide Names
Unique 64 bit identifier.
Static to the port.– Used to physically identify a port or node within the SAN.– Similar to NIC MAC address
Additionally, each node is assigned a unique port ID (address) within the SAN– Used to communicate between nodes within the SAN– Similar in functionality to an IP address on a NIC.
World Wide Names: Example
World Wide Name - HBA
1 0 0 0 0 0 0 0 c 9 2 0 d c 4 0Reserved
12 bitsCompany OUI
24 bitsCompany Specific
24 bits
World Wide Name – Array
5 0 0 6 0 1 6 0 0 0 6 0 0 1 B 20101 0000 0000 0110 0000 0001 0110 0000 0000 0000 0110 0000 0000 0001 1011 0010
Company ID24 bits
Port Model seed 32 bits
Fibre Channel Addressing
Fibre Channel addresses are used for transporting frames from source ports to destination ports.
Address assignment method varies with the associated topology (loop vs switch)– Loop – self assigning
– Switch – centralized authority
Certain addresses are reserved – FFFFFC is Name Server
– FFFFFE is Fabric Login
What is a Fabric?
Virtual space used by nodes to communicate with each other once they are joined.
Component identifiers:– Domain ID
– Worldwide Name (WWN)
Fabric
Fibre Channel Topologies
Arbitrated Loop (FC-AL)– Devices attached to a shared
“loop”
– Analogous to Token Ring
Switched Fabric (FC-SW)– All devices connected to a “Fabric
Switch” – Analogous to an IP switch
– Initiators have unique dedicated I/O paths to Targets
Switch
HUB
Switch versus Hub Comparison
Switches (FC-SW)– FC-SW architecture scalable to
millions of connections.
– Bandwidth per device stays constant with increased connectivity.
– Bandwidth is scalable due to dedicated connections.
– Higher availability than hubs.
Hubs (FC-AL)– FC-AL is limited to 127
connections (substantially fewer connections can be implemented for ideal system performance).
– Bandwidth per device diminishes with increased connectivity due to sharing of connections.
– Low cost connection.
Topology: Mesh Fabric
Can be either partial or full mesh
All switches are connected to each other
Host and Storage can be located anywhere in the fabric
Host and Storage can be localized to a single switch
Partial Mesh Full Mesh
Full Mesh Benefits and Tradeoffs
Benefits– All storage/servers are maximum of one ISL hop away.
– Hosts and storage may be located anywhere in the fabric.
– Multiple paths for data using the Fabric Shortest Path First (FSPS) algorithm.
– Fabric management made simpler.
Topology: Simple Core-Edge Fabric
Can be two or three tiers– Single Core Tier– One or two Edge Tiers
In a two tier topology, storage is usually connected to the Core
Benefits– High Availability– Medium Scalability– Medium to maximum
ConnectivityStorage Tier
Host Tier
Core-Edge Benefits
Simplifies propagation of fabric data.– One ISL hop access to all storage in the fabric.
Efficient design based on node type.– Traffic management and predictability.
Easier calculation of ISL loading and traffic patterns.
Lesson: Summary
Topics in this lesson included:
The Fibre Channel SAN connectivity methods and topologies
Fibre Channel devices
Fibre Channel communication protocols
Fibre Channel login procedures
Lesson: SAN Management
Upon completion of this lesson, you will be able to:
Describe SAN management functions– Infrastructure protection
– Provisioning
– Capacity Management
– Performance Management
SAN Management Overview
Infrastructure protection
Fabric Management
Storage Allocation
Capacity Tracking
Performance Management
Infrastructure Security
Physical security– Locked data center
Centralized server and storage infrastructure– Controlled administrator access
Storage Arrays
Switch Switch
Secure VPNor
FirewallServers
Control Station
Corporate LAN
Management LAN (Private)
In-band (FC)
Out-band (IP)
Switch/Fabric Management Tools
Vendor supplied management software– Embedded within the switch
– Graphical User Interface (GUI) or Command Line Interface (CLI)
Functionality– Common functions
Performance monitoringDiscoveryAccess Management (Zoning)
– Different “look and feel” between vendors
Additional third party software add-ons– Enhanced functionality, such as automation
Fabric Management: Zoning
Zoning Components
Zone Zone ZoneZones
(Library)
Zone SetZones Sets(Library)
Members(WWN’s) Member Member Member MemberMember Member
Provisioning: LUN Masking
Restricts volume access to specific hosts and/or host clusters.
Servers can only access the volumes that they are assigned.
Access controlled in the storage and not in the fabric– Makes distributed administration
secure
Tools to manage masking– GUI– Command Line
Capacity Management
Tracking and managing assets – Number of ports assigned
– Storage allocated
Utilization profile– Indicates the percent usage of a given resource over time
– Allows for forecasting
SAN management software provides the tools– Inventory databases
– Report writers
Performance Management
What is it?– Capturing metrics and monitoring trends
– Proactively or Reactively responding
– Planning for future growth
Areas and functions– Host, Fabric and Storage Performance
– Building baselines for the environment
Lesson: Summary
Topics in this lesson included:– Infrastructure protection
– Provisioning
– Capacity Management
– Performance Management
Internet ProtocolStorage Area Networks (IP SAN)
Internet ProtocolStorage Area Networks (IP SAN)
Module 3.4
IP Storage Area Networks
Upon completion of this module, you will be able to:
Describe the benefits of IP SAN.
Describe IP convergence in the SAN and its implications.
Describe and discuss the basic architecture of – FCIP
– iFCP
– iSCSI
Explain potential applications of IP SAN technology.
In this module …
This module contains the following lessons:
IP SAN Overview.
IP SAN Protocols.
Applications of IP SAN.
Lesson: IP SAN Overview
Upon completion of this lesson, you will be able to:
Describe the benefits of IP SAN.
Describe the IP convergence in the SAN and its implications.
List the three common IP SAN approaches.
List the three deployment models (topologies) for IP SAN.
Introduction
Traditional SAN technology is built around Fibre Channel.
IP technology is emerging as an alternative or supplemental transport for storage traffic.
= IP= FC
FCFC IPIP IPIP FCFCIP
FC/IP
FC/IP
FC/IP
FC/IP
IP
IP/ FCIP/ FC
IP/FCIP/FC
Block Storage over IP – Protocol options
iSCSI– SCSI over IP
IP encapsulation done on host / HBA(host bus adapter)
Hardware-based gateway to Fibre Channel storage
FCIP– Fibre Channel-to-IP bridge /
tunnel (pointto point) Fibre Channel end points
iFCP– IP as the inter-switch fabric
Fibre Channel end points
IPIPIP
IPIP FCFC
IP Storage Approaches
iSCSI
FCFC
FC
FC
FC
IPNetwork
IPNetwork
IPNetwork
IPNetwork
iFCPFCIP
iFCP Switch
iFCPSwitch
FCIP Router
FCIP Router iSCSI/FC Gateway
Market Drivers for SAN Internetworking
Fibre Channel SAN challenges.
IP SAN enablers.
Easy to leverage IP equipment and expertise to help manage data in conjunction with Fibre Channel SANs.
Benefits of IP SAN
Cost Effective
Extend the reach of a SAN
IP is Cost Effective
Most organizations already have IP networks and familiarity with traditional network management.
Leverages existing Fibre Channel applications.
Extend the Reach of Your SAN
Standard Fibre Channel Distances.
IP Extends Fibre Channel applications over regional/global distances.
At higher link speeds, IP can handle synchronous applications.
Lesson Summary
Topics in this lesson included:
Describe the benefits of IP SAN.
Describe the IP convergence in the SAN and its implications.
List the three common IP SAN approaches.
List the three deployment models (topologies) for IP SAN.
Lesson: IP SAN Protocols
Upon completion of this lesson, you will be able to:
Describe and discuss the basic architecture of – FCIP
– iFCP
– iSCSI
Fibre Channel over IP - FCIP
Encapsulates FC frames in IP packets.
Creates virtual FC links that connect devices and fabric elements.
Includes security, data integrity, congestion and performance specifications.
IP Datagram
IPHeader
TCPHeader
FCIPHeader IP PayloadIP Payload
Fibre Channel Frame
SO
F FCHeader C
RC
EO
F
SCSI DataSCSI Data
FCIP EncapsulationFCIP Encapsulation
FCIP Benefits
FCIP – Best of both technologies
– Support for existing applications
– Cost effective
– Multi-point networking
Fibre Channel• Widely available• Low latency• High reliability • Off-the-shelf solutions• Mature standards
IP• Widely available• Accepted technology• Trained user base• Affordable• Mature standards
Internet Fibre Channel Protocol - iFCP
Gateway-to-gateway protocol– IP switches & routers replace FC switches
– Transparent to FC drivers
FC transport uses TCP connections– Point-to-multipoint networking possible
IPHeader
TCPHeader
iFCPHeader IP PayloadIP Payload
Fibre Channel Frame
SO
F FCHeader C
RC
EO
F
SCSI DataSCSI Data
iFCP Address Translation &Encapsulation
iFCP Address Translation &Encapsulation
iFCP Benefits
Works with wide range of devices.
Flexible.
Less potential bottlenecking vs. FCIP.
iSCSI
A method to transfer blocks of data using the TCP/IP network.
Serialized service delivery subsystem.
SCSI protocol over IP.
iSCSI Model Layers
IPHeader
TCPHeader
iSCSIHeader IP PayloadIP Payload
SCSI DataSCSI Command Descriptor
SCSI CDB encapsulation
IP Datagram
Storage
Lesson Summary
Topics in this lesson included:
The basic architecture of FCIP.
The basic architecture of iFCP.
The basic architecture of iSCSI.
Content Addressed Storage (CAS)Content Addressed Storage (CAS)
Module 3.5
Content Addressed Storage (CAS)
Upon completion of this module, you will be able to:
Describe the features and benefits of a CAS based storage strategy.
List the physical and logical elements of CAS.
Describe the storage and retrieval process for CAS data objects.
Describe the best environments for CAS solutions.
In this Module …
This module contains the following lessons:
CAS Description and Benefits
Elements of CAS
Data Object Storage and Retrieval
CAS Applications and Case Scenarios
Lesson: CAS Description and Benefits
Upon completion of this lesson, you be able to:
Define CAS.
Describe the key attributes of CAS.
List the features, benefits and drawbacks of CAS.
What is Content Addressed Storage (CAS)?
Object-oriented, location-independent approach to data storage.
Repository for the “Objects”.
Access mechanism to interface with repository.
Globally unique identifiers provide access to objects.
Extensible metadata that enables automated data management practices and applications.
What Is Fixed Content?
Electronic Documents• Contracts, claims, etc.
• E-mail and attachments
• Financial spread sheets
• CAD/CAM designs
• Presentations
Digital Records
• Documents– Checks, securities trades– Historical preservation
• Photographs– Personal / professional
• Geophysical– Seismic, astronomic,
geographic
Digital Assets Retained For Active Reference And ValueDigital Assets Retained For Active Reference And Value
Leverage Historical Value
Improve Service Levels
Generate New Revenues
Rich Media
• Medical– X-rays, MRIs, CTI
• Video– News / media, movies– Security serveillance
• Audio– Voicemail– Radio
Challenges of Storing Fixed Content
Most new digital content is fixed content.
Fixed content is growing at more than 90% annually.
Long-term preservation is required (years-decades).
Simultaneous multi-user access.
Need for faster access to records for business and legal reasons.
Need for location independent data, enabling technology refresh and migration.
Emerging regulations require retention.
Traditional storage methods are inadequate.
Shortcomings of Traditional Storage Options
Tape is slow, and standards are always changing.
Optical is expensive, and requires vast amounts of media in order to store data of any size.
Many times companies retire tape products without warning.
Many times recovering files from tape and optical is time consuming.
Data on tape and optical is subject to media degradation.
Benefits of CAS
Immutability and authentication
Location independence
Single instance storage
Faster record retrieval
Record-level retention,protection and disposition
Technology independence
Online (like Disk)
Optimized TCO
Scalability
Drawbacks of CAS
There are some drawbacks with CAS:
Can be slower than SAN, NAS, or DAS.
Application integration.
Initial cost of ownership is higher even though TCO is significantly lower.
Lesson: Summary
Key points covered in this lesson:
CAS Definition
CAS Description
Benefits and Drawbacks
Lesson: Elements of CAS
Upon completion of this lesson, you will be able to:
Describe the Physical Elements of CAS.
Describe the Logical Elements of CAS.
Storage devices (CAS Based)
Servers (to which storage devices get connected)
Client
Physical Elements of CAS
API
ServerClient CAS-basedStorage
Logical Elements of CAS
The Logical Elements of CAS include the Object-Level Access Protocols.
CAS
API
API
Metadata
39HLTTT2H0404EU6M4A9MUR7TE4
Content Address
Lesson Summary
Key points covered in this lesson:
Physical Elements of CAS
Logical Elements of CAS
Lesson: Data Object Storage and Retrieval
Upon completion of this lesson, you will be able to:
Describe how data gets stored in a CAS environment.
Describe how data is retrieved from a CAS environment.
How CAS Stores a Data Object
API
Application Server
Client
CAS
Object ID
Client presents datato API to be archived
1
Unique ContentAddress is calculated
2
Object is sent to CASvia CAS API over IP
3
CAS authenticates theContent Address and
stores the object
4
Acknowledgementreturned to application
5
Object-ID is retainedand stored for future use
6
How CAS Retrieves a Data Object
Application Server
Client
CAS
Object is needed byan application
1 CAS authenticatesthe request and
delivers the object
4
Application findsContent Address of
object to be retrieved
2 Retrieval request issent to the CAS via
CAS API over IP
3
API
Object ID
Lesson: Summary
Key points covered in this lesson:
How data gets stored in a CAS environment.
How data is retrieved from a CAS environment.