4. SAN PROTOCOL STACK
TRANSPORT LAYER-> SCSI PROTOCOL
NETWORK LAYER- >FCP OR ISCSI
DATA LINK LAYER-> FCoE/ iFCP
PHYSICAL LAYER- >ETHERNET CABLE/
FIBER CHANNEL LINK
5. FC SAN ISCSI FCOE
Ninad Chaubal and Abhash Malviya
6. FIBER CHANNEL SAN
• Speeds of 16 Gbps.
• FC switch is a crucial junction.
• Every server will have a HBA (Host Bus Adaptor).
• FC Switch is better known as Fabric
• Storage arrays usually have dual ports to support multipathing.
7. LOSSLESS TRANSMISSION IN FC SAN
Every switch maintains a buffer
counter.
An acknowledgment frame is
generated by the target.
This ensures that every frame is
accounted for.
8. BENEFITS OF FC SAN
FC SAN is robust and has faster processing speeds.
FC SAN is hot-swappable.
Storage Resources can be centrally managed and storage space can be
allocated and reallocated as per requirements.
9. IP BASED SAN
ISCSI is an internet protocol based storage
network
ISCSI has a client/Server model
Client is the initiator
Server is the target
Works on 10Gbps link
A 16 Gbps Fiber Channel cable can carry
more amounts of data in one second as
compared to a 10 Gbps Ethernet cable in
one second.
ISCSI
12. FCOE
Unify FC and Ethernet
Ethernet: scalability ,simplification
FC: Functionality, Manageability, Lossless Nature
Reduces the cost
Consolidates the input-output
Turn WWPN to MAC address
13. FCOE and FIP packet format
LAN uses NIC
Ethernet uses MAC
CNA (Convergence Network Adapter)
FIP sets up the communication between
host/target to witch
ports on the hosts and the storage sites are known
as ‘VN_Ports’
ports between two switches are known as
‘VE_Ports’
ports between a switch and a host/storage
(server) is known as ‘VF_Port’
FIP it is designed to prevent unauthorized access
and data transmission on FC
FIP snooping is enabled on VLANs
15. Data transfer method :
CIFS(Common Internet file system)
Implements client/server method
Functions of CIFS: Get access to files , share files, automatic restoration of
connection
Implements TCP/IP protocol
Runs as application layer network protocol
NFS(Network File System)
Allows users on client server to access files on network
Different versions : NFSv2,NFSv3,NFSv4
16. VMFS( Virtual Machine File System)
Allows multiple VMware vSphere to read and write simultaneously.
Ability to add or delete a vSphere host without disturbing other host
Create new virtual machine independently
Simplify storage management
17. STORAGE:
Disk System
Tape System
STORAGE AREA CONNECTIVITY
Small Computer System Interface (SCSI)
Fibre Channel
Lower Level :Ethernet
Middle Level :
Internet Small Computer System Interface (iSCSI)
Fibre Channel Protocol over IP (FCIP)
Higher Level :
NAS- NFS ( Network File System)
CIFS (Common Internet File System)
SERVER
Mainframe Server
UNIX based servers
19. Speed: Up to 10 Gbps for iSCSI and up to 16 Gbps for Fibre Channel.
Cost Effective: iSCSI is almost always cost effective as compared to Fibre
Channel.
Complexity: Fibre Channel is more complex to setup initially.
iSCSI vs FC SAN
Storage space of each of the storage units are consolidated together to form a storage pool known as the Storage Area Network (SAN)
storage space is divided into logical storage blocks (Figure 9) which can span multiple storage drives and storage systems.
application servers are connected to the consolidated Storage Network
say server A, needs some storage space, a portion of the storage pool is allocated to the individual servers. This basically means a group of logical storage blocks, that may span many different physical drives in the storage pool, is assigned to the server.
storage space is now reserved for Server A and is mounted on server A as a drive.
Server F wants to access the same data of Server A, it is possible without having to copy the entire data as Server F can access the same devices on which the data of Server A is physically located.
we only need to change the ownership of the storage “drive” from server A to server F, by changing management permissions, to ensure that server A does not write data into the logical “drive” while server F is actively working on it.
any client machine can access any data from the storage pool by connecting to any of the application servers.
SAN provides Universal storage connectivity which eliminates the need for frequent data transfers between servers
no need to worry about application servers sharing data to be synchronized as the same copy of data is being accessed by each.
logical allocation of storage space to application servers, it’s not necessary that all the space comes from the same physical hard drive
unallocated blocks maybe reserved for expansion space to be allocated to another application server.
Fiber Channel is a high speed, bi directional network technology.
A FC SAN network can reach up to speeds of 16 Gbps.
FC switch is a crucial junction in the SAN Network.
Every server will have a HBA (Host Bus Adaptor).
This HBA could be multi port or single port. But to ensure high availability a multi port HBA is preferable.
In case our HBA is a single port HBA, we need must have two single port HBA ports to implement multipathing.
FC Switch better known as Fabric, is responsible for handling multipathing as well as routing the servers to the appropriate destination.
Last but not the least the storage arrays usually have dual ports to support multipathing.
Lossless frame transmission can be achieved in FC SAN.
Every switch maintains a buffer counter which keeps decrementing the buffer count as and when the buffer space starts filling up with frames.
An acknowledgment frame from the target switch tells the sender switch that the frame has been successfully received.
This ensures that every frame is accounted for since there is an acknowledgement for every frame received.
FC SAN is robust and has faster processing speeds due to the Fiber cables used it has faster processing speed.
FC SAN is hot-swappable e.g. (multiple power supplies, two controller cards for high availability)
It is hot swappable since if a part goes bad, there is no down time and process continues without any delay.
Storage Resources can be centrally managed and storage space can be allocated and reallocated as per requirements.
In ISCSI the target exports the block device and the client imports the block device. In iscsi the target server can be divided into multiple targets having a unique ID corresponding to SAN. There are multiple LUNs that is Logical unit number it’s a storage device or u can say more of a hard drive that are attach to the target logically or physically
CIFS stands for Common internet file system. It is client/server model in which client sends request to server program to access file or pass msg to application on server. It implements TCP/IP protocol. It runs on application layer network protocol provides shared access to files printers and serial ports. It offers authenticated process. NFS : Is practically used for Linux and Unix operating system. Used for remote access. User can change or delete information in one computer by using another computer. CIFS is windows based. It is more talkative as it initiates a request for accessing file on another computer that is connected to server PC. Then this server computer will make a response. CIFS has broader scope a s it allows shared access to various application such as printer. NFS is simple in implementation . There are three types of NFS : NFSv2 : runs only on udp and supports 32 bit files. Only 1st 2 gb of file can be read. NFSv3 : Supports 64 bit files also supports asynchronous writes on server. NFSv4: improved performance and provides security.
Acronym for virtual machine file system. It is optimized for virtual machines. In conventional file system only one server is used for read and write access to same file system at a particular time. While VMFS allows multiple VMware VSphere host to read and write simultaneously. Allows adequate storage for virtual machine and also takes care of future storage equipment's. It simplifies storage management with automatic discovery and mapping LUNs to VMFS volumes.
DISK System: has central control unit that manages all I/O
Simplifies integration of system with other services and can customize the size of the system depending on specific functionality of a particular Storage system.
TAPE system: similar to disk system
Types of tape: Tape Drives: tapes are connected to one another tape by providing logical and physical structure for reading from and writing to tape.
Tape Autoloader: These are autonomous tape drives that perform automatic backup.
Tape Libraries: Can manage multiple tape simultaneously. Used where there is massive storage requirement.
Server: Mainframe : single, monolithic multiprocessor high performance computer system
Unix : it has Unix operating system.
Switches: 10 gig: full duplex pt to pt link which can be CU and FC
FC San Switch: these are compatible with FC protocol that allows many to many communication, security redundancy. It implements Zoning i.e. disable unwanted traffic between the nodes.
