Any vendor's switch will starts with 8 ports, 16 ports, 24 ports and 48 ports. 8 ports will come like a socket which can easily insert on a switch and every port is a licensed one. If we want to procure a 8 ports socket we have to contact to the switch vendor and have to buy the ports with license. The rate of data transfer in a switch is 8 GB/sec at max, if we need to increase the speed we have to do the trunking/ISL. We can also change the port speed to 2, 4, 8 Gb/sec & auto mode. In a switch the major activity will be the Zoning and also we do trouble shooting, ISL, Port Channeling and other works. Zoning means “Grouping of Host HBA WWPN and Storage Front End Ports WWPN to speak each other.” It uses the Server HBA WWN number and Storage Front End Port WWN number. It’s also known as WWN Zoning. A major advantage of WWN Zoning is its flexibility. It allows the SAN to be recabled without re configuring the Zone information. Below are the models for your reference Brocade: Switches: 6510, 6505, 5300, 5100, VA-40FC, 5000, 4900, 2400, 2800, 3800, 3900, 4100, 300, 200E Directors: DCX 8510-8, DCX 8510-4, DCX, DCX-4S, 48000, 24000, 12000 Cisco: Switches: Cisco MDS 9020, 9120, 9124, 9124e, 9134, 9140, 9148, 9216, 9216A, 9216i, 9222i, and 9250i Directors: Cisco MDS 9506, 9509, 9513, and 9710
Mc-Data: Switches: 3232, 4500, 4700 Directors: 6064, 6140, 10000
Components of an Intelligent Storage System An intelligent storage system consists of four key components: front end, cache, back end, and physical disks. An I/O request received from the host at the front-end port is processed through cache and the back end, to enable storage and retrieval of data from the physical disk. A read request can be serviced directly from cache if the requested data is found in cache. front-end ports The front-end ports enable hosts to connect to the intelligent storage system. back end ports The back end controls data transfers between cache and the physical disks. From cache, data is sent to the back end and then routed to the destination disk. Physical disks are connected to ports on the back end. Read Operation with Cache When a host issues a read request, the front-end controller accesses the TAG RAM to determine whether the required data is available in cache. If the requested data is found in the cache, it is called a read cache hit or read hit. Read performance is measured in terms of the read hit ratio, or the hit rate, usually expressed as a percentage. This ratio is the number of read hits with respect to the total number of read requests. A higher read hit ratio improves the read performance. Fibre Channel Ports Ports on the switch can be one of the following types: N_port: An end point in the fabric. This port is also known as the node port.
Typically, it is a host port (HBA) or a storage array port that is connected to a switch in a switched fabric. NL_port: A node port that supports the arbitrated loop topology. This port is also known as the node loop port. E_port: An FC port that forms the connection between two FC switches. This port is also known as the expansion port. The E_port on an FC switch connects to the E_port of another FC switch in the fabric through a link, which is called an Inter-Switch Link (ISL). ISLs are used to transfer host-tostorage data as well as the fabric management traffic from one switch to another. ISL is also one of the scaling mechanisms in SAN connectivity. F_port: A port on a switch that connects an N_port. It is also known as a fabric port and cannot participate in FC-AL. FL_port: A fabric port that participates in FC-AL. This port is connected to the NL_ports on an FC-AL loop. A FL_port also connects a loop to a switch in a switched fabric. As a result, all NL_ports in the loop can participate in FC-SW. This configuration is referred to as a public loop. In contrast, an arbitrated loop without any switches is referred to as a private loop. A private loop contains nodes with NL_ports, and does not contain FL_port. G_port: A generic port that can operate as an E_port or an F_port and determines its functionality automatically during initialization. World Wide Names Each device in the FC environment is assigned a 64-bit unique identifier called the World Wide Name (WWN). The Fibre Channel environment uses two types of WWNs: World Wide Node Name (WWNN) and World Wide Port Name (WWPN).
