Fabric OS Administrator’s Guide 3
53-1001763-02
Chapter
1

Understanding Fibre Channel Services

In this chapter
Fibre Channel services overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
The Management Server. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Platform services. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Management server database . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Topology discovery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Device login . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
High availability of daemon processes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Fibre Channel services overview

Fibre Channel services define service functions such as the Name Server, Management Server,
Security Key Distribution Server, and Time Server. Every Brocade switch has reserved three-byte
addresses referred to as well-known addresses. These services provided by Brocade switches
reside at these addresses and provide a service to either nodes or management applications in the
fabric.
FIGURE 1 Well-known addresses
Fabric Login — The Fabric Login server assigns a fabric address. This allows a fabric node to
communicate with services on the switch or other nodes in the fabric. The fabric address assigned
to a nodes is a 24-bit address (0x000000) containing three - 3-byte long nodes. Reading from left
to right, the first node (0x000000), represents the domain ID, the second node (0x000000) the
port area number of the port where the node is attached, and the third node (0x000000) the
arbitrated loop physical address (AL_PA), if applicable.
Directory Server — The Directory Server or Name Server is used to register fabric and public nodes
and query to discover other devices in the fabric.
Fabric Controller — The Fabric Controller provides State Change Notifications (SCNs) to registered
nodes when a change in the fabric topology occurs.
Time Server — The Time Server sends to the member switches in the fabric the time on either the
principal switch or the primary Fabric Configuration Server (FCS) switch.