System and method for implementing multiple IP addresses on multiple ports

• US 6,061,349 A
• Filed: 05/02/1997
• Issued: 05/09/2000
• Est. Priority Date: 11/03/1995
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Kersey, Edward C., Coile, Brantley W., Howes, Richard A.
• Primary Examiner(s): CANGIALOSI, SALVATORE A
• Application Number:
  US08/850,730
• Time in Patent Office: 1,103 Days
• Field of Search: 370/389, 370/392, 370/400, 370/401, 370/402, 370/475, 709/219, 709/226, 709/228, 709/229, 709/227, 709/238
• US Class Current: 370/389
• CPC Class Codes: H01R 2201/04 for network, e.g. LAN connectors
• CPC Class Codes: H01R 31/005 Intermediate parts for distributing signals
• CPC Class Codes: H04L 2101/663 Transport layer addresses, e.g. aspects of transmission control protocol [TCP] or user datagram protocol [UDP] ports
• CPC Class Codes: H04L 41/00 Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/2514 between local and global IP addresses
• CPC Class Codes: H04L 61/2564 for a higher-layer protocol, e.g. for session initiation protocol [SIP]
• CPC Class Codes: H04L 63/0254 Stateful filtering
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

Disclosed is a system and method for handling a plurality of connection requests made for a plurality of virtual machines with a single physical machine. A system and method are disclosed for distributing virtual connections among a plurality of physical machines some or all of which are configured to handle connections for more than one virtual machine. In one embodiment, a packet translation system for handling connections from clients on an external network to a plurality of IP addresses with a server having a server IP address and a server port number includes a client interface to the external network. The client interface is operative to receive and send packets to and from a remote client. A server interface is operative to receive and send packets to and from the server and the server is operative to establish a connection with the remote client. A packet interceptor is operative to intercept incoming packets received at the client interface which have a packet destination IP address and a packet destination port number corresponding to a virtual machine IP address and a virtual machine port number which is supported by the packet translation system. A packet header translator is operative to translate the packet destination IP address and the packet destination port number of packets forwarded by the packet interceptor to a physical machine IP address and a physical machine port number that corresponds to the server IP address and the server port number of the server. The server port runs a real process corresponding to a virtual process simulated on the virtual port number. As a result, the packet translation system receives packets at the client interface and the packet destination IP address and the packet destination port number corresponding to the virtual machine IP address and the virtual machine port number are translated to the server IP address and the server port number and the packets are forwarded to the server via the server interface.

Claims

1. A packet translation system for handling connections from clients on an external network to a plurality of IP addresses with a server having a server IP address and a server port number comprising:

a client interface to the external network, the client interface being operative to receive and send packets to and from a remote client;

a server interface to an internal network, the server interface being operative to receive and send packets to and from the server, the server being operative to establish a connection with the remote client;

a packet interceptor which is operative to intercept incoming packets received at the client interface which have a packet destination IP address and a packet destination port number corresponding to a virtual machine IP address and a virtual machine port number which is supported by the packet translation system;

a packet header translator which is operative to translate the packet destination IP address and the packet destination port number of packets forwarded by the packet interceptor to a physical machine IP address and a physical machine port number that corresponds to the server IP address and the server port number of the server, the server port running a real process corresponding to a virtual process simulated on the virtual port number;

whereby the packet translation system receives packets at the client interface and the packet destination IP address and the packet destination port number corresponding to the virtual machine IP address and the virtual machine port number are translated to the server IP address and the server port number and the packets are forwarded to the server via the server interface.

2. A system as recited in claim 1, further including a connection database which includes for each connection handled by the packet translation system, a connection object that stores a connection source IP address and a connection source port number, a connection virtual machine IP address and a connection virtual machine port number, and a connection physical machine IP address and a connection physical machine port number, whereby the connection database provides all of the information required to translate the packet headers.

3. A system as recited in claim 2, wherein the connection objects are stored in a linked list.

4. A system as recited in claim 3 wherein the connection objects are searched upon the receipt of an incoming packet using a hash of the connection source IP address and the connection virtual machine IP address.

5. A system as recited in claim 1, further including a virtual machine database including a plurality of virtual machine objects, each virtual machine object including a virtual machine object IP address and a virtual machine object port number for a virtual machine supported by the packet translation system.

6. A system as recited in claim 5 wherein the plurality of virtual machine objects are stored in a linked list.

7. A system as recited in claim 1, further including a physical machine database including a plurality of physical machine objects including a physical machine object IP address for each physical machine available to the packet translation system.

8. A system as recited in claim 7 wherein the plurality of physical machine objects are stored in a linked list.

9. A system as recited in claim 1 wherein the packet interceptor rejects packets having a packet destination IP address which corresponds to a virtual machine IP address of one of the virtual machines supported by the packet translation system and having a packet destination port which does not correspond to a virtual machine port of one of the virtual machines supported by the packet translation system.

10. A system as recited in claim 1, wherein the packet interceptor is further operative to intercept outgoing packets received at the server interface, the outgoing packets having a packet source IP address and a packet source port number and wherein the packet header translator is further operative to translate the packet source IP address and the packet source port number of outgoing packets to a physical machine IP address and a physical machine port number that corresponds to the server IP address and the server port number of the server which runs a real process corresponding to a virtual process simulated on the virtual port number.

11. A packet translation system for handling connections from clients on an external network to a plurality of IP addresses with a plurality of servers on an internal network, the plurality of servers having a plurality of server IP addresses and a plurality of server port numbers comprising:

a client interface to the external network, the client interface being operative to receive and send packets to and from a remote client;

a server interface to the internal network, the server interface being operative to receive and send packets to and from a server, the server being operative to establish a connection with the remote client;

a connection distributor which is operative to distribute connections to a selected server having a selected server IP address and a selected server port number from the plurality of servers;

a packet interceptor which is operative to intercept incoming packets received at the client interface which have a packet destination IP address and a packet destination port number corresponding to a virtual machine IP address and a virtual machine port number which is supported by the packet translation system;

a packet header translator which is operative to translate the packet destination IP address and the packet destination port number of incoming packets to a physical machine IP address and a physical machine port number that corresponds to the selected server IP address and the selected server port number which runs a real process corresponding to a virtual process simulated on the virtual port number;

whereby the packet translation system receives packets at the client interface and the packet destination IP address and the packet destination port number corresponding to the virtual machine IP address and the virtual machine port number are translated to the server IP address and the server port number and the packets are forwarded to the server via the server interface.

12. A system as recited in claim 11, wherein the connection distributor distributes connections to a selected server from the plurality of servers which is predicted to be the fastest server for handling the connection.

13. A method for handling connections from clients on an external network to a plurality of IP addresses with a server having a server IP address and a plurality of server port numbers, each port number corresponding to a distinct one of the plurality of IP addresses comprising:

receiving an incoming packet from a remote client, the incoming packet having a packet destination IP address and a packet destination port number corresponding to a virtual machine IP address and a virtual machine port number which is supported by the server;

translating the packet destination IP address and the packet destination port number of incoming packets to a physical machine IP address and a physical machine port number that corresponds to the server IP address and the server port number of the server, the server running a real process corresponding to a virtual process simulated on the virtual port number;

forwarding the packet to the server, the server being operative to establish a connection with the remote client;

whereby packets are received and the packet destination IP address and the packet destination port number corresponding to the virtual machine IP address and the virtual machine port number are translated to the server IP address and the server port number and the packets are forwarded to the server.

14. A method as recited in claim 13, further including:

creating a connection database which includes for each connection, a connection object that stores a connection source IP address and a connection source port number, a connection virtual machine IP address and a connection virtual machine port number, and a connection physical machine IP address and a connection physical machine port number, whereby the connection database provides all of the information required to translate the packet headers.

15. A method as recited in claim 14, wherein the connection objects are stored in a linked list.

16. A method as recited in claim 14 further including searching the connection objects upon the receipt of an incoming packet using a hash of the connection source IP address and the connection virtual machine IP address.

17. A method as recited in claim 13, further including creating a virtual machine database including a plurality of virtual machine objects, each virtual machine object including a virtual machine object IP address and a virtual machine object port number for a virtual machine supported by the server.

18. A method as recited in claim 17 wherein the plurality of virtual machine objects are stored in a linked list.

19. A method as recited in claim 13, further including creating a physical machine database including a plurality of physical machine objects including a physical machine object IP address for plurality of physical machines.

20. A method as recited in claim 19 wherein the plurality of physical machine objects are stored in a linked list.

21. A method as recited in claim 13 further including rejecting packets having a packet destination IP address which corresponds to a virtual machine IP address of one of the virtual machines supported by the server and having a packet destination port which does not correspond to a virtual machine port of one of the virtual machines supported by the server.

22. A method as recited in claim 13, further including intercepting outgoing packets received at a server interface, the outgoing packets having a packet source IP address and a packet source port number;

and translating the packet source IP address and the packet source port number of outgoing packets to a physical machine IP address and a physical machine port number that corresponds to the server IP address and the server port number of the server running a real process corresponding to a virtual process simulated on the virtual port number.

23. A packet translation system for forwarding a packet to a server having a server IP address and two or more server ports, each corresponding to a distinct one of two or more defined virtual IP addresses, the packet having a packet destination IP address matching one of the two or more defined virtual IP addresses, the packet translation system comprising:

a client interface to an external network, the client interface being operative to receive packets from a remote client;

a server interface to the server, the server interface being operative to send packets to the server, the server being operative to handle packets sent from the remote client; and

a packet translator which is operative to translate the packet destination IP address to the server IP address and to provide a destination port address to the packet, which destination port address is selected from the two or more ports and corresponds to the packet destination IP address.