H3C Technologies H3C S5830V2 Series Switches - Manual (Page 38)

27
Configuring VSANs
The virtual storage area network (VSAN) technology breaks a physical SAN into multiple VSANs, and
provides more secure, reliable, and flexible services.
Devices in a VSAN cannot get information about any other VSAN and devices in any other VSAN. Each
VSAN performs the following operations independently:
• Selecting a principal switch.
• Assigning domain IDs.
• Running routing protocols.
• Maintaining routing table and FIB table.
• Providing services.
The VSAN technology delivers the following benefits:
• Improved security—VSANs are isolated from each other.
• Improved scalability—Each VSAN independently runs and provides services. Different VSANs can
use the same address space so that network scalability is improved.
• Flexibility—You can assign interfaces to different VSANs without changing the physical
connections of the SAN.
VSAN fundamentals
The interfaces in a VSAN can work as access ports or trunk ports.
• Access port—An access port can belong to only one VSAN.
• Trunk port—A trunk port can belong to multiple VSANs.
FC interfaces can work as access ports or trunk ports, depending on negotiation.
VFC interfaces can only work as trunk ports.
Access VSAN
Figure 16 shows a typical access VSAN:
• The ports of blue links on switches (including E_Ports and F_Ports) are configured as access ports
and assigned to VSAN 1.
• The ports of purple links are configured as access ports and assigned to VSAN 2.
When servers read the disks, the N_Ports of different servers send FC frames to the F_Ports on FC Switch
A. Switch A searches for the outgoing interfaces in the FIB table of the VSAN that each F_Port belongs
to. These F_Ports use different E_Ports as outgoing interfaces. Packets are forwarded out of these E_Ports,
and they might travel across multiple VSAN-capable switches to the E_Ports of FC Switch B.
Switch B searches for the outgoing interfaces in the FIB tables of the VSAN that each E_Port belongs to,
and forwards them to the F_Ports. Then, the F_Ports send the frames to the N_Ports of different disk
devices. The frames from the disk devices to the server are processed in the same way and finally reach
the servers.