Storage router and method for routing IP datagrams between data path processors using a fibre channel switch

• US 7,295,572 B1
• Filed: 03/26/2003
• Issued: 11/13/2007
• Est. Priority Date: 03/26/2003
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Haapala, Clayton S.
• Primary Examiner(s): NGUYEN, BRIAN D
• Application Number:
  US10/403,219
• Time in Patent Office: 1,693 Days
• Field of Search: 370/466, 370/401
• US Class Current: 370/466
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]

Abstract

A storage router includes an IP network interface with IP network ports and data path processors. Each of the data path processors may control one of the IP network ports. High speed communication links couple the data path processors with a fiber channel switch. The storage router may route IP datagrams between the data path processors using the fiber channel switch. The fiber channel switch switches fiber channel packets between the data path processors and a plurality of fiber channel switch ports. The fiber channel packets may be encapsulated IP datagrams. Fiber channel packets received at a data path processor may be re-encapsulated and sent back through the fiber channel switch to another data path processor when the packets are destined for IP addresses associated with IP network ports controlled by other data path processors. Among other things, asymmetric data paths, and multiple and redundant communication paths with host systems are supported.

Claims

1. A storage router comprising:

an IP network interface having a plurality of IP network ports;

a plurality of data path processors, wherein each one of the data path processors controls at least one of the IP network ports; and

a fibre channel switch to switch fibre channel packets between the data path processors and a plurality of fibre channel switch ports,

wherein when a destination address of a fibre channel packet received at a first of the data path processors is an IP address associated with an IP network port controlled by another data path processor, the first data path processor modifies at least a portion of the packet to identify a fibre channel switch port associated with the another data path processor and transfers the modified fibre channel packet to the fibre channel switch which switches the modified fibre channel packet to the fiber channel switch port associated with the another data path processor.

2. The storage router of claim 1 wherein at least some of the fibre channel switch ports are data path processor ports,

wherein the storage router further comprises a high speed communication link coupling each the data path processor with one of the data path processor ports, and

wherein other of the fibre channel switch ports are fibre channel network ports to couple with a fibre channel network.

3. The storage router of claim 2 wherein the fibre channel switch receives fibre channel packets from the data path processors at the data path processor ports, and receives fibre channel packets from the fibre channel network at the fibre channel network ports, the fibre channel switch to switch the received packets between any of the data path processor ports and the fibre channel network ports.

4. The storage router of claim 3 wherein when the destination address of the fibre channel packet received at the first data path processor is an IP address associated with an IP network port controlled by the first data path processor, the first data path processor to encapsulate at least a portion of the packet as an internet small computer systems interface (iSCSI) protocol data unit (PDU) within a TCP/IP datagram, the first data path processor to transfer the datagram as an Ethernet frame to the controlled IP network port.

5. The storage router of claim 4 wherein when the destination address of an IP packet received at the first data path processor is a fibre channel address within the fibre channel network, the first data path processor to encapsulate at least a portion of the IP packet as a fibre channel packet to identify one of the fibre channel network ports, the first data path processor to transfer the fibre channel packet to the fibre channel switch, the fibre channel switch to route the fibre channel packet to the identified fibre channel network port.

6. The storage router of claim 3 wherein the IP network interface provides at least first and second communication paths between a host system and the storage router respectively with first and second IP network ports, the first IP network port being controlled by the first data path processor, the second IP network port being controlled by a second of the data path processors, the first and second communication paths comprising an asymmetric data path.

7. The storage router of claim 6 wherein when the first data path processor receives a fibre channel packet having a destination associated with the first IP network port, and when the first communication path with the host is operational:

the first data path processor to encapsulate at least a portion of the packet as an internet small computer systems interface (iSCSI) protocol data unit (PDU) within a TCP/IP packet, and the first data path processor to transfer the TCP/IP packet as an Ethernet frame to the first IP network port.

8. The storage router of claim 2 wherein the high speed communication links are first high speed communication links, and

wherein the storage router further comprises a second high speed communication link coupling each data path processor to the IP network interface, each of the second high speed communication links being associated with at least one of the IP network ports.

9. The storage router of claim 8 further comprising a control processor to provide control information to each of the data path processors, the control processor coupled to the data path processors by control links.

10. The storage router of claim 1 wherein the fibre channel switch is a crossbar switch.

11. The storage router of claim 1 wherein the IP network interface receives Ethernet frames over an IP network, the Ethernet frames being IP datagrams,

wherein the fibre channel packets include a fibre channel header identifying one of the fibre channel switch ports and a small computer systems interface (SCSI) portion, and

wherein the Ethernet frames comprise a TCP/IP packet with an Ethernet header, the TCP/IP packet including an internet small computer system interface (iSCSI) portion wrapped around the SCSI portion.

12. The storage router of claim 11 wherein the SCSI portion comprises command sets and associated data to control devices in the storage router, the SCSI portion being stored on the devices in the storage router, the iSCSI portion comprising protocols to implement communications between a host system and the storage router over a TCP/IP network.

13. A storage router comprising:

an IP network interface having a plurality of IP network ports;

a plurality of data path processors, wherein each one of the data path processors control at least one of the IP network ports; and

a fibre channel switch to switch fibre channel packets between the data path processors and a plurality of fibre channel switch ports,

wherein at least some of the fibre channel switch ports are data path processor ports,

wherein the storage router further comprises a high speed communication link coupling each data path processor with one of the data path processor ports,

wherein other of the fibre channel switch ports are fibre channel network ports to couple with a fibre channel network,

wherein the fibre channel switch receives fibre channel packets from the data path processors at the data path processor ports, and receives fibre channel packets from the fibre channel network at the fibre channel network ports, the fibre channel switch to switch the received packets between any of the data path processor ports and the fibre channel network ports,

wherein when a destination address of a fibre channel packet received at a first of the data path processors is an IP address associated with an IP network port controlled by the first data path processor, the first data path processor to encapsulate at least a portion of the packet as an internet small computer systems interface (iSCSI) protocol data unit (PDU) within a TCP/IP datagram, the first data path processor to transfer the datagram as an Ethernet frame to the controlled IP network port, and

wherein when the destination address of the fibre channel packet is an IP address associated with another IP network port controlled by another data path processor, the first data path processor to modify at least a portion of the packet, the modified fibre channel packet to identify the fibre channel switch port associated with the another data path processor, the first data path processor to transfer the modified fibre channel packet to the fibre channel switch, the fibre channel switch to switch the packet to the data path processor port of the fibre channel switch associated with the another data path processor.

14. A storage router comprising:

an IP network interface having a plurality of IP network ports;

a plurality of data path processors, wherein each one of the data path processors control at least one of the IP network ports; and

a fibre channel switch to switch fibre channel packets between the data path processors and a plurality of fibre channel switch ports,

wherein at least some of the fibre channel switch ports are data path processor ports,

wherein the storage router further comprises a high speed communication link coupling each data path processor with one of the data path processor ports,

wherein other of the fibre channel switch ports are fibre channel network ports to couple with a fibre channel network,

wherein the fibre channel switch receives fibre channel packets from the data path processors at the data path processor ports, and receives fibre channel packets from the fibre channel network at the fibre channel network ports, the fibre channel switch to switch the received packets between any of the data path processor ports and the fibre channel network ports,

wherein the IP network interface provides at least first and second communication paths between a host system and the storage router respectively with first and second IP network ports, the first IP network port being controlled by a first of the data path processors, the second IP network port being controlled by a second of the data path processors, the first and second communication paths comprising an asymmetric data path, and

wherein when the first data path processor receives a fibre channel packet having a destination associated with the first IP network port, and when the first communication path with the host is operational;

the first data path processor to encapsulate at least a portion of the packet as an internet small computer systems interface (iSCSI) protocol data unit (PDU) within a TCP/IP packet, and the first data path processor to transfer the TCP/IP packet as an Ethernet frame to the first IP network port, and

wherein when the first communication path with the host is non-operational;

the first data path processor to modify at least a portion of the fibre channel packet, the modified fibre channel packet to identify the fibre channel switch port associated with the second data path processor and to identify the second IP network port, the first data path processor to transfer the modified fibre channel packet to the fibre channel switch, the fibre channel switch to switch the packet to the data path processor port of the fibre channel switch associated with the second data path processor for receipt by the second data path processor, the second data path processor to encapsulate at least a portion of the modified fibre channel packet as an iSCSI PDU within a TCP/IP packet, and the second data path processor to transfer the TCP/IP packet as an Ethernet frame to the second IP network port.

15. A method of routing packets within a storage router comprising:

when a destination of a packet is an IP address associated with an IP network port controlled by a data path processor, the method includes;

encapsulating at least a portion of the packet as an Ethernet frame; and

transferring the packet to the controlled IP network port, and

when the destination is an IP address associated with an IP network port controlled by another data path processor, the method includes;

encapsulating at least a portion of the packet as a fibre channel packet to identify a fibre channel switch port associated with the another data path processor; and

transferring the packet over a high-speed communication link to a fibre channel switch, the fibre channel switch to switch the fibre channel packet to the identified fibre channel switch port for receipt by the another data path processor.

16. The method of claim 15 when the destination is a fibre channel address in a fibre channel network, the method comprises:

encapsulating the packet as a fibre channel packet to identify a fibre channel switch port associated with the fibre channel address; and

transferring the packet over the high-speed communication link to the fibre channel switch, the switch to switch the fibre channel packet to the identified fibre channel switch port for transfer to the fibre channel network.

17. The method of claim 16 further comprising:

providing at least first and second communication paths between a host system and a IP network interface of the storage router respectively with first and second IP network ports, the first IP network port being controlled by a first of a plurality of data path processors, the second IP network port being controlled by a second of the data path processors.

18. The method of claim 17 further comprising:

receiving at the first data path processor a fibre channel packet having a destination associated with the first IP network port, and when the first communication path with the host is operational;

encapsulating, by the first data path processor at least a portion of the packet as an internet small computer systems interface (iSCSI) protocol data unit (PDU) within a TCP/IP packet; and

transferring the TCP/IP packet as an Ethernet frame to the first IP network port.

19. The method of claim 18 wherein when the first communication path with the host is non-operational, the method includes the first data path processor:

modifying at least a portion of the fibre channel packet, the modified fibre channel packet to identify the fibre channel switch port associated with the second data path processor and to identify the second IP network port;

transferring the modified fibre channel packet to the fibre channel switch, the fibre channel switch to switch the packet to a data path processor port of the fibre channel switch associated with the second data path processor for receipt by the second data path processor,

the method further including the second data path processor;

encapsulating at least a portion of the modified fibre channel packet as an iSCSI PDU within a TCP/IP packet; and

transferring the TCP/IP packet within an Ethernet frame to the second IP network port.

20. An article comprising a computer-readable storage medium having stored thereon instructions, that when executed by a digital computing platform, result in routing packets within a storage router including when a destination of a packet is an IP address associated with an IP network port controlled by a data path processor by:

encapsulating at least a portion of the packet as an Ethernet frame; and

transferring the packet to the controlled IP network port, and

when the destination is an IP address associated with an IP network port controlled by another data path processor, the instructions result in;

encapsulating at least a portion of the packet as a fibre channel packet to identify a fibre channel switch port associated with the another data path processor; and

transferring the packet over a high-speed communication link to a fibre channel switch, the fibre channel switch to switch the fibre channel packet to the identified fibre channel switch port for receipt by the another data path processor.

21. The article of claim 20 wherein the instructions, when further executed by the digital computing platform result in, when the destination is a fibre channel address in a fibre channel network:

encapsulating the packet as a fibre channel packet to identify a fibre channel switch port associated with the fibre channel address; and

transferring the packet over the high-speed communication link to the fibre channel switch, the switch to switch the fibre channel packet to the identified fibre channel switch port for transfer to the fibre channel network.

22. The article of claim 21 wherein the instructions, when further executed by the digital computing platform result in:

providing at least first and second communication paths between a host system and a IP network interface of the storage router respectively with first and second IP network ports, the first IP network port being controlled by a first of a plurality of data path processors, the second IP network port being controlled by a second of the data path processors;

receiving at the first data path processor a fibre channel packet having a destination associated with the first IP network port, and when the first communication path with the host is operational;

encapsulating, by the first data path processor at least a portion of the packet as an internet small computer systems interface (iSCSI) protocol data unit (PDU) within a TCP/IP packet; and

transferring the TCP/IP packet as an Ethernet frame to the first IP network port.

23. A system comprising:

means for encapsulating; and

means for transferring,

wherein when a destination of a packet is an IP address associated with an IP network port controlled by a data path processor, the means for encapsulating encapsulates at least a portion of the packet as an Ethernet frame, and the means for transferring transfers the packet to the controlled IP network port, and

wherein when the destination is an IP address associated with an IP network port controlled by another data path processor, the means for encapsulating encapsulates at least a portion of the packet as a fibre channel packet to identify a fibre channel switch port associated with the another data path processor, and the means for transferring transfers the packet over a high-speed communication link to a fibre channel switch, the fibre channel switch to switch the fibre channel packet to the identified fibre channel switch port for receipt by the another data path processor.

24. The system of claim 23 when the destination is a fibre channel address in a fibre channel network, the means for encapsulating encapsulates the packet as a fibre channel packet to identify a fibre channel switch port associated with the fibre channel address, and the means for transferring transfers the packet over the high-speed communication link to the fibre channel switch, the switch to switch the fibre channel packet to the identified fibre channel switch port for transfer to the fibre channel network.

25. The system of claim 24 further comprising:

means for providing at least first and second communication paths between a host system and a IP network interface of a storage router respectively with first and second IP network ports, the first IP network port being controlled by a first of a plurality of data path processors, the second IP network port being controlled by a second of the data path processors.

26. The system of claim 25 further comprising:

means for receiving at the first data path processor a fibre channel packet having a destination associated with the first IP network port, and when the first communication path with the host is operational, the means for encapsulating encapsulates at least a portion of the packet as an internet small computer systems interface (iSCSI) protocol data unit (PDU) within a TCP/IP packet, and the means for transferring transfers the TCP/IP packet as an Ethernet frame to the first IP network port.