Method and system for using extended fabric features with fibre channel switch elements
View Patent ↗A fiber channel switch element and method for routing fiber channel frames is provided. The switch element includes a receive segment that can add a virtual storage area network (“VSAN”) tagging header to frames that are received by the receive segment; and strip the VSAN tagging header before frames are sent to ports that do not support virtual fabric capability. The receive segment includes a table used for matching fabric extension parameters. An incoming frame's VSAN identity value is compared to a control word entry to generate a value used for routing the incoming frame. The table is used to determine if a frame is part of a virtual fabric. The routing table for each port is used to route frames and the routing table includes entries for supported virtual fabrics.
1. A method for routing a frame received at a receive segment of a port of a network device, comprising:
(a) determining if support for routing the frame in a virtual storage area network (“VSAN”) is enabled at the port of the network device;
(b) when the frame includes a VSAN identifier, comparing the VSAN identifier of the frame with a plurality of entries stored for the port;
(c) when there is a match with one of the entries, then setting an indicator indicating that a match was found;
(d) using the VSAN identifier for determining a destination port;
(e) determining if VSAN encapsulation mode is enabled for adding a tagging header to the frame; wherein the tagging header includes the VSAN identifier value for identifying the VSAN; and
(f) when VSAN encapsulation mode is enabled, then adding the tagging header to the frame, before routing the frame to the destination port.
2. The method of claim 1 , wherein the VSAN routing capability is enabled by setting a value in a control register.
3. The method of claim 1 , wherein different virtual port identifier values are used for different virtual fabrics to the route the frame.
4. The method of claim 1 , wherein the tagging header is based on an entry from a control register for the port.
5. The method of claim 1 , wherein an error message is generated if the comparison in step (b) of claim 1 produces multiple matches.
6. A network device, comprising:
a port having a receive segment, the network device being configured to
(a) when a frame is received at the receive segment, determine if support for routing the frame in a virtual storage area network (“VSAN”) is enabled at the port;
(b) when the frame includes a VSAN identifier, compare the VSAN identifier of the frame with a plurality of entries stored for the port;
(c) when there is a match with one of the entries, then set an indicator indicating that a match was found;
(d) use the VSAN identifier for determining a destination port;
(e) determine if VSAN encapsulation mode is enabled for adding a tagging header to the frame; wherein the tagging header includes the VSAN identifier value for identifying the VSAN; and
(f) when VSAN encapsulation mode is enabled, then add the tagging header to the frame, before routing the frame to the destination port.
7. The network device of claim 6 , wherein the VSAN routing capability is enabled by setting a value in a control register.
8. The network device of claim 6 , wherein different virtual port identifier values are used for different virtual fabrics to the route the frame.
9. The network device of claim 6 , wherein the tagging header is based on an entry from a control register for the port.
10. The network device of claim 6 , wherein an error message is generated if the comparison in step (b) of claim 6 produces multiple matches.