Fabric Login types in switched network

Fabric services have three login types as explained below:

FLOGI also known as Fabric Login. Performed between a N_Port and a F_Port. To log on to the fabric, a node sends a FLOGI frame with the WWNN and WWPN parameters to the login service at the pre-defined FC address FFFFFE (Fabric Login Server). In turn, the switch accepts the login and returns an Accept (ACC) frame with the assigned FC address for the node. Immediately after the FLOGI, the N_Port registers itself with the local Name Server on the switch, indicating its WWNN, WWPN, port type, class of service, assigned FC address and so on. After the N_Porth as logged in, it can query the name server database for information about all other logged in ports.

PLOGI also known as Port Login. Performed between two N_Ports to establish a session. The initiator N_Portsends a PLOGI request frame to the target N_Port, which accepts it. The target N_Port returns an ACC to the initiator N_Port. Next, the N_Ports exchange service parameters relevant to the session.

PRLI also known as Process Login. performed between two N_Ports. This login relates to the FC-4 ULPs, such as SCSI. If the ULP is SCSI, N_Portsexchange SCSI-related service parameters.

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