What is FLOGI PLOGI and PRLI In SAN Switch
What is FLOGI PLOGI and PRLI In SAN Switch read this blog and you will get the answer. This blog has detail explanation of three device login process on SAN switch. Basically there are three device login process FLOGI, PLOGI and PRLI.
What is Device Login In SAN Switch ?
Device Login is a series of process which happens when a new node or devices is connected to a Fabric. Once Device Login Process Completes then a device can communicate with other devices in same fabric. Its Involves three steps FLOGI PLOGI and PRLI.Components of Device Login In SAN Switch
Host – These are the server which are connected to Switch.Array – These are the storage Array connected to Switch
SAN Switch – A SAN switch having FC Ports
Not only above three devices any other device which connects to SAN switch with FC protocol has to go through device login process..
What is FLOGI Process in SAN switch network
FLOGI Process happens when a new device is connected to switch or fabric for the first time. Once the device is power the device sends it first frame to the switch where it is connected. The first frame contains some information like WWPN and buffer to buffer credits (B2B credits).The switch reads these information and then assign a 24 bit Unique ID address to device. This unique ID called as FCID. Switch uses this FCID to identify the end device connected to it in SAN network. Then the end device also confirms to the switch that it received FCID.
What is PLOGI SAN Switch Network.
Port initialization in PLOGI Process in SAN Switch
PLOGI Process has two port initialization and registration in Name Server. During port initialization information like port type and port speed are exchanged between end device or host and SAN switch. SAN switch use these information and negotiate with host. During negotiation SAN switch will come to know whether the end device is a server or a storage by referencing the port type.What is Name Server In SAN Switch Network
During Name Server registration of PLOGI process the device register its information in Name server. This provides information to device about all other device which are registered in name server that it can communicate to.Each fabric is SAN switch network maintains a name server. These name server contains the information of every devices connected to the SAN Fabric. Two device in SAN switch network can communicate only if both of them are Name server.
What is PRLI Process Login In SAN Switch
PRLI also stands for process Login. During this process actual communication happens between device connected to switch which are present in Name Server. In simple terms we can say that a during PRLI N_port communicates with another N_Port. In broad term a host communicates with storage array.During PRLI process a host sends a PRLI request to storage array. If proper zoning and LUN masking is exists then storage array accept the PRLI request and start a communication between them.
Device Login Process SAN Switch With Diagram
Below is a diagram which explains step by step process of Device login in SAN switch network. Subscribe the blog for more such article.
