Methods, systems and computer program products for port assignments of multiple application instances using the same source IP address

• US 7,120,697 B2
• Filed: 05/22/2001
• Issued: 10/10/2006
• Est. Priority Date: 05/22/2001
• Status: Active Grant

• Current Assignee: A10 Networks Incorporated
• Original Assignee: International Business Machines Corporation
• Inventors: Herr, David Anthony, Devine, Wesley McMillan, Aiken, John Andrew Jr., McClintock, Mark W., Ward, Raymond E.
• Primary Examiner(s): VU, VIET DUY
• Application Number:
  US09/862,968
• Publication Number:
  US 20020178268A1
• Time in Patent Office: 1,967 Days
• Field of Search: 709/219, 709/225, 709/226, 709/227, 709/228, 709/229, 709/238, 709/249, 709/250
• US Class Current: 709/229
• 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 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/10015 Access to distributed or replicated servers, e.g. using brokers
• CPC Class Codes: H04L 67/1023 based on a hash applied to IP addresses or costs
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

Methods, systems and computer program products provide assignment of ports for connections originated by multiple application instances executing on different data processing systems utilizing a common network address. An indication of available ports for the common network address is provided to each of the different data processing systems executing the multiple application instances. A port identified as available is selected as a port for a connection utilizing the common network address.

Claims

1. A method of assigning a port for a connection originated by one of multiple application instances, the multiple application instances executing on different data processing systems and utilizing a common network address, comprising:

providing an indication of available ports for the common network address to each of the different data processing systems executing the multiple application instances; and

selecting a port identified as available as the port for the connection utilizing the common network address, wherein providing an indication of available ports comprises maintaining an identification of available ports associated with the common network address in a storage accessible by each of the multiple data processing systems; and

wherein selecting a port comprises selecting a port identified as available in the storage accessible by each of the data processing systems.

2. The method of claim 1, wherein the step of selecting a port identified as available is responsive to the one of the multiple applications requesting to establish a connection utilizing the common network address as a source address for the connection.

3. The method of claim 1, wherein the common network address is a virtual Internet Protocol address.

4. The method of claim 1, wherein the identification of available ports comprises an identification of ports associated with existing connections utilizing the common network address such that ports which are not identified as associated with existing connections are identified as available.

5. The method of claim 1, further comprising establishing the connection utilizing the selected port and the common network address as a source network address and port of the connection.

6. The method of claim 5, wherein establishing the connection further comprises identifying the selected port as unavailable in the storage accessible by each of the data processing systems.

7. The method of claim 6, further comprising:

terminating the connection utilizing the selected port and the common network address; and

identifying the selected port as available in the storage accessible by each of the data processing systems.

8. The method of claim 1, wherein the different data processing systems comprise a Sysplex and the storage accessible by each of the data processing systems comprises a coupling facility.

9. The method of claim 8, wherein the steps of maintaining an identification of available ports associated with the common network address in a storage accessible by each of the data processing systems and selecting a port identified as available in the storage accessible by each of the data processing systems are carried out by communication protocol stacks of the data processing systems.

10. The method of claim 9, wherein the step of maintaining an identification of available ports associated with the common network address further comprises:

maintaining a first structure in the coupling facility which indicates whether the port is available for assignment by any of the communication protocol stacks; and

maintaining a second structure in the coupling facility for each of the communication protocol stacks which indicates which ports are in use by the corresponding communication protocol stack.

11. A method of assigning a port for a connection originated by one of multiple application instances, the multiple application instances executing on different data processing systems and utilizing a common network address, comprising:

providing an indication of available ports for the common network address to each of the different data processing systems executing the multiple application instances; and

selecting a port identified as available as the port for the connection utilizing the common network address;

wherein providing an indication of available ports comprises maintaining an identification of available ports associated with the common network address in a storage accessible by each of the multiple data processing systems;

wherein selecting a port comprises selecting a port identified as available in the storage accessible by each of the data processing systems;

wherein the different data processing systems comprise a Sysplex and the storage accessible by each of the data processing systems comprises a coupling facility;

wherein the steps of maintaining an identification of available ports associated with the common network address in a storage accessible by each of the data processing systems and selecting a port identified as available in the storage accessible by each of the data processing systems are carried out by communication protocol stacks of the data processing systems; and

wherein the step of maintaining an identification of available ports associated with the common network address further comprises;

maintaining a first structure in the coupling facility which indicates whether the port is available for assignment by any of the communication protocol stacks; and

maintaining a second structure in the coupling facility for each of the communication protocol stacks which indicates which ports are in use by the corresponding communication protocol stack;

detecting a failure of one of the communication protocol stacks; and

revising the first structure based on the second structure corresponding to the failed communication protocol stack so as to indicate that the ports in used by the failed communication protocol stack are available for use.

12. A method of coordinating port assignments for connections utilizing a dynamic virtual Internet Protocol address (DVIPA) as a source address, wherein the DVIPA is utilized as a source address for connections originated by a plurality of data processing systems, comprising:

maintaining an indication of available ports associated with the DVIPA in a storage facility which is commonly accessible to communication protocol stacks of the plurality of data processing systems; and

selecting a port for a connection utilizing the DVIPA as a source address based on the indication of available ports associated with the DVIPA in the storage facility, wherein maintaining an indication of available ports and selecting a port are carried out by the communication protocol stacks of the plurality of data processing systems and wherein maintaining an indication of available ports and selecting a port are selectively carried out by the communication protocol stacks responsive to a predefined keyword being provided in a configuration statement which defines the DVIPA to the communication protocol stack.

13. The method of claim 12, wherein maintaining an indication of available ports associated with the DVIPA comprises maintaining a structure in a coupling facility of a Sysplex, the structure indicating whether a port is in use by a connection utilizing the DVIPA as a source address.

14. The method of claim 13, wherein selecting a port comprises:

accessing the coupling facility to obtain the structure; and

evaluating the structure to select a port which is not in use by a connection.

15. The method of claim 14, further comprising updating the structure in the coupling facility to reflect that the selected port is in use by a connection utilizing the DVIPA as a source address.

16. The method of claim 14, wherein accessing the coupling facility and updating the coupling facility comprise:

obtaining the structure from the coupling facility;

locking the structure in the coupling facility to prevent access to the structure by other communication protocol stacks;

then

revising the structure to reflect that the selected port is in use;

returning the structure to the coupling facility; and

then

unlocking the structure in the coupling facility to allow access to the structure by other communication protocol stacks.

17. The method of claim 16, wherein the structure comprises a bitmap and wherein revising the structure comprises setting a bit of the bitmap to a predefined value to indicate that a port corresponding to the bit is in use.

18. The method of claim 16, wherein the structure comprises an enumerated list of available ports and wherein revising the structure comprises removing selected port from the enumerated list.

19. The method of claim 12, wherein the configuration statement is at least one of a VIPADEFine statement, a VIPADISTribute statement and a VIPARANGE statement.

20. The method of claim 12, further comprising updating the indication of available ports to reflect existing connections using the DVIPA if the predefined keyword is added to a configuration statement after initialization of a routing communication protocol stack.

21. The method of claim 13, wherein maintaining a structure in a coupling facility further comprises updating the structure in the coupling facility to reflect that a port of a connection utilizing the DVIPA as a source address is not in use when the connection utilizing the DVIPA as a source address terminates.

25. The method of claim 12, wherein maintaining an indication of available ports associated with the DVIPA comprises maintaining a copy of a connection routing hash table associated with the DVIPA in a coupling facility of a Sysplex, the connection routing hash table indicating source address and source port and destination address and destination port for connections utilizing the DVIPA.

26. The method of claim 25, wherein selecting a port comprises:

determining a connection routing hash table entry for a source address and source port and a destination address and destination port of a connection utilizing the DVIPA as a source address;

evaluating the connection routing hash table in the coupling facility to determine if an entry exists corresponding to the determined connection routing hash table entry; and

selecting the port utilized in determining the connection routing hash table entry if a corresponding entry does not exist.

27. The method of claim 25, further comprising updating the connection routing hash table in the coupling facility to incorporate the determined connection routing hash table entry.

29. The method of claim 25, wherein maintaining a copy of a connection routing hash table in a coupling facility further comprises updating the connection routing hash table in the coupling facility to reflect that a connection utilizing the DVIPA as a source address is not in use when the connection utilizing the DVIPA as a source address terminates.

31. The method of claim 12, wherein the step of maintaining an indication of available ports further comprises:

maintaining a first structure in the storage facility which indicates whether the port is available for assignment by any of the communication protocol stacks; and

maintaining a second structure in the storage facility for each of the communication protocol stacks which indicates which ports are in use by the corresponding communication protocol stack.

22. A method of coordinating port assignments for connections utilizing a dynamic virtual Internet Protocol address (DVIPA) as a source address, wherein the DVIPA is utilized as a source address for connections originated by a plurality of data processing systems, comprising:

maintaining an indication of available ports associated with the DVIPA in a storage facility which is commonly accessible to communication protocol stacks of the plurality of data processing systems; and

selecting a port for a connection utilizing the DVIPA as a source address based on the indication of available ports associated with the DVIPA in the storage facility;

wherein maintaining an indication of available ports and selecting a port are carried out by the communication protocol stacks of the plurality of data processing systems;

wherein maintaining an indication of available ports associated with the DVIPA comprises maintaining a structure in a coupling facility of a Sysplex, the structure indicating whether a port is in use by a connection utilizing the DVIPA as a source address;

wherein maintaining a structure in a coupling facility further comprises updating the structure in the coupling facility to reflect that a port of a connection utilizing the DVIPA as a source address is not in use when the connection utilizing the DVIPA as a source address terminates; and

wherein updating the structure in the coupling facility comprises;

obtaining the structure from the coupling facility;

locking the structure in the coupling facility to prevent access to the structure by other communication protocol stacks;

then

revising the structure to reflect that the port associated with the terminated connection is not in use;

returning the structure to the coupling facility; and

then

unlocking the structure in the coupling facility to allow access to the structure by other communication protocol stacks.

23. The method of claim 22, wherein the structure comprises a bitmap and wherein revising the structure comprises setting a bit of the bitmap to a predefined value to indicate that a port corresponding to the bit is not in use.

24. he method of claim 22, wherein the structure comprises an enumerated list of available ports and wherein revising the structure comprises adding the port associated with the terminated connection to the enumerated list.

28. A method of coordinating port assignments for connections utilizing a dynamic virtual Internet Protocol address (DVIPA) as a source address, wherein the DVIPA is utilized as a source address for connections originated by a plurality of data processing systems, comprising:

maintaining an indication of available ports associated with the DVIPA in a storage facility which is commonly accessible to communication protocol stacks of the plurality of data processing systems; and

selecting a port for a connection utilizing the DVIPA as a source address based on the indication of available ports associated with the DVIPA in the storage facility;

wherein maintaining an indication of available ports and selecting a port are carried out by the communication protocol stacks of the plurality of data processing systems;

wherein maintaining an indication of available ports associated with the DVIPA comprises maintaining a copy of a connection routing hash table associated with the DVIPA in a coupling facility of a Sysplex, the connection routing hash table indicating source address and source port and destination address and destination port for connections utilizing the DVIPA, the method further comprising updating the connection routing hash table in the coupling facility to incorporate the determined connection routing hash table entry; and

wherein evaluating the connection routing hash table and updating the connection routing hash table comprise;

obtaining the connection routing hash table from the coupling facility;

locking the structure in the coupling facility to prevent access to the connection routing hash table by other communication protocol stacks;

then

incorporating the determined connection routing hash table entry into the connection routing hash table;

returning the connection routing hash table to the coupling facility; and

then

unlocking the connection routing hash table in the coupling facility to allow access to the connection routing hash table by other communication protocol stacks.

30. A method of coordinating port assignments for connections utilizing a dynamic virtual Internet Protocol address (DVIPA) as a source address, wherein the DVIPA is utilized as a source address for connections originated by a plurality of data processing systems, comprising:

maintaining an indication of available ports associated with the DVIPA in a storage facility which is commonly accessible to communication protocol stacks of the plurality of data processing systems; and

selecting a port for a connection utilizing the DVIPA as a source address based on the indication of available ports associated with the DVIPA in the storage facility;

wherein maintaining an indication of available ports and selecting a port are carried out by the communication protocol stacks of the plurality of data processing systems;

wherein maintaining an indication of available ports associated with the DVIPA comprises maintaining a copy of a connection routing hash table associated with the DVIPA in a coupling facility of a Sysplex, the connection routing hash table indicating source address and source port and destination address and destination port for connections utilizing the DVIPA;

wherein maintaining a copy of a connection routing hash table in a coupling facility further comprises updating the connection routing hash table in the coupling facility to reflect that a connection utilizing the DVIPA as a source address is not in use when the connection utilizing the DVIPA as a source address terminates; and

wherein updating the connection routing hash table in the coupling facility comprises;

obtaining the connection routing hash table from the coupling facility;

locking the connection routing hash table in the coupling facility to prevent access to the connection routing hash table by other communication protocol stacks;

then

revising the connection routing hash table to remove an entry corresponding to the terminated connection;

returning the connection routing hash table to the coupling facility; and

then

unlocking the connection routing hash table in the coupling facility to allow access to the connection routing hash table by other communication protocol stacks.

32. A method of coordinating port assignments for connections utilizing a dynamic virtual Internet Protocol address (DVIPA) as a source address, wherein the DVIPA is utilized as a source address for connections originated by a plurality of data processing systems, comprising:

maintaining an indication of available ports associated with the DVIPA in a storage facility which is commonly accessible to communication protocol stacks of the plurality of data processing systems; and

selecting a port for a connection utilizing the DVIPA as a source address based on the indication of available ports associated with the DVIPA in the storage facility;

wherein the step of maintaining an indication of available ports further comprises;

maintaining a first structure in the storage facility which indicates whether the port is available for assignment by any of the communication protocol stacks; and

maintaining a second structure in the storage facility for each of the communication protocol stacks which indicates which ports are in use by the corresponding communication protocol stack;

detecting a failure of one of the communication protocol stacks; and

revising the first structure based on the second structure corresponding to the failed communication protocol stack so as to indicate that the ports in used by the failed communication protocol stack are available for use.