Global server load balancing support for private VIP addresses

• US 20100095008A1
• Filed: 09/29/2003
• Published: 04/15/2010
• Est. Priority Date: 09/29/2003
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Foundry Networks Incorporated (Broadcom, Inc.)
• Inventors: Joshi, Prajakta S.
• Granted Patent: US 9,584,360 B2
• Time in Patent Office: Days
• US Class Current: 709/228
• CPC Class Codes: H04L 61/2514 between local and global IP addresses
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers

Abstract

A site switch determines the mapping between public and private IP addresses of VIPs configured on the site switch. The site switch then transmits the public IP address, rather than the private IP address, to a load balancing switch that performs the load balancing for network resources accessible via the site switch. This public IP address has also been configured on an authoritative DNS server for which the load balancing switch serves as a proxy. The load balancing switch updates its address records, containing the VIPs configured on the site switch, with the public address of the VIP. When the load balancing switch reorders a DNS reply from the authoritative DNS server for a domain containing the public address, the load balancing switch correctly identifies the IP address as a VIP on the site switch and applies appropriate load balancing metrics to the received IP address.

Claims

1-33. -33. (canceled)

34. A method of providing load balancing usable with a load balance switch and a plurality of site switches that are each adapted to couple at least one host server to a network, the method comprising:

obtaining at one of said site switches mapping information that provides a translation between a private virtual IP address, configured at said site switch and associated with said at least one host server corresponding to said site switch, and a public virtual IP address; and

providing, by said site switch, said public virtual IP address to at least one load balancing controller.

35. The method of claim 34 wherein said providing, by said site switch, said public virtual IP address to said at least one load balancing controller includes providing by said site switch said public virtual IP address to a load balancing controller located at said load balance switch.

36. The method of claim 35 wherein said providing, by said site switch, said public virtual IP address to said at least one load balancing controller further includes providing by said site switch said public virtual IP address to a load balancing controller located at said site switch, to enable said site switch to balance traffic among plural ones of said at least one host server corresponding to said site switch and associated with said private virtual IP address.

37. The method of claim 34 wherein public virtual IP addresses received by said load balancing controller as part of reply to a query for network addresses and that do not have indication in an address record as being associated with corresponding said site switches, are treated as real IP addresses by said load balancing controller and are excluded from having applied thereto any metric of a load balancing algorithm that is usable with virtual IP addresses.

38. The method of claim 34 wherein said public virtual IP address provided to said at least one load balancing controller enables said load balancing controller to apply at least one metric of a load balancing algorithm to said public virtual IP address, said at least one metric including an active bindings metric that prefers a virtual IP address, configured at respective said site switches, having a maximum number of active ones of said host servers bound to said preferred virtual IP address, rather than preferring another virtual IP address having a number of bound active ones of said host servers that is less than said maximum number.

60. The method of claim 34 wherein said obtaining at said site switch said mapping information includes obtaining at said site switch said mapping information from a mapping device that includes a network address translation device or a firewall device.

39-42. -42. (canceled)

43. An article of manufacture, comprising:

a storage medium at a site switch and having instructions stored thereon that are executable by said site switch to enable load balancing, by;

obtaining at said site switch mapping information that provides a translation between a private virtual IP address and a public virtual IP address, said private virtual IP address being configured at said site switch and being associated with at least one host server corresponding to said site switch; and

providing, by said site switch, said public virtual IP address to at least one load balancing controller.

44. The article of manufacture of claim 43 wherein the instructions to provide, by said site switch, said public virtual IP address to said at least one load balancing controller includes instructions to provide by said site switch said public virtual IP address to a load balancing controller located at said load balance switch.

45. The article of manufacture of claim 43 wherein the instructions to provide, by said site switch, said public virtual IP address to said at least one load balancing controller includes instructions to provide by said site switch said public virtual IP address to a load balancing controller located at said site switch, to enable said site switch to balance traffic among plural ones of said at least one host server corresponding to said site switch and associated with said private virtual IP address.

46. The article of manufacture of claim 43 wherein said public virtual IP address provided to said at least one load balancing controller enables said load balancing controller to apply at least one metric of a load balancing algorithm to said public virtual IP address, said at least one metric including an active bindings metric that prefers a virtual IP address, configured at respective said site switches, having a maximum number of active ones of said host servers bound to said preferred virtual IP address, rather than preferring another virtual IP address having a number of bound active ones of said host servers that is less than said maximum number.

61. The article of manufacture of claim 43 wherein said instructions to obtain at said site switch said mapping information includes instructions to obtain at said site switch said mapping information from a mapping device that includes a network address translation device or a firewall device.

47-50. -50. (canceled)

51. A network device, comprising:

a site switch configurable with a private virtual IP address associated with at least one host server corresponding to said site switch; and

a component in said site switch to obtain a public virtual IP address translated from said private virtual IP address,

wherein said site switch is adapted to provide said obtained public virtual IP address to at least one load balancing controller.

52. The network device of claim 51 wherein said at least one load balancing controller includes a load balancing controller located at a load balance switch remote from said site switch.

53. The network device of claim 51 wherein said at least one load balancing controller includes a load balancing controller located at said site switch and adapted to balance traffic among plural ones of said at least one host server corresponding to said site switch and associated with said private virtual IP address.

54. The network device of claim 51 wherein public virtual IP addresses received by said load balancing controller as part of reply to a query for network addresses and that do not have indication in an address record as being associated with a corresponding one of a plurality of said site switch, are treated as real IP addresses by said load balancing controller and are excluded from having applied thereto any metric of a load balancing algorithm that is usable with virtual IP addresses.

55. The network device of claim 51 wherein said public virtual IP address provided to said at least one load balancing controller enables said load balancing controller to apply at least one metric, usable with virtual IP addresses, of a load balancing algorithm to said public virtual IP address, said at least one metric including an active bindings metric that prefers a virtual IP address, configured at respective plural ones of said site switch, having a maximum number of active ones of said host servers bound to said preferred virtual IP address, rather than preference of another virtual IP address having a number of bound active ones of said host servers that is less than said maximum number.

62. The network device of claim 51 wherein said component in said site switch is adapted to obtain said public virtual IP address from a mapping device that includes a network address translation device or a firewall device.

56-59. -59. (canceled)

63. A method of providing load balancing, the method comprising:

identifying, by a switch, a public virtual IP address that is mapped to a private virtual IP address configured at the switch; and

communicating, by the switch to a load balancing controller, the identified public virtual IP address.

64. The method of claim 63 wherein said communicating includes:

sending, by the switch, the identified public virtual IP address to the load balancing controller, which is located at the switch.

65. The method of claim 63 wherein said identifying the public virtual IP address that is mapped to the private virtual IP address includes:

identifying, by the switch, the public virtual IP address from mapping information internally stored in the site switch.

66. The method of claim 63 wherein said identifying the public virtual IP address that is mapped to the private virtual IP address includes:

identifying, by the switch, the public virtual IP address from mapping information externally received by the site switch.

67. An article of manufacture, comprising:

a storage medium at a switch and having instructions stored thereon that are executable by the switch to;

identify, by the switch, a public virtual IP address that is mapped to a private virtual IP address configured at the switch; and

communicate, by the switch to a load balancing controller, the identified public virtual IP address.

68. The article of manufacture of claim 67 wherein the instructions executable by the switch to communicate include instructions executable by the switch to:

send, by the switch, the identified public virtual IP address to the load balancing controller, which is located at the switch.

69. The article of manufacture of claim 67 wherein the instructions executable by the switch to identify the public virtual IP address that is mapped to the private virtual IP address include instructions executable by the switch to:

identify, by the switch, the public virtual IP address from mapping information internally stored in the site switch.

70. The article of manufacture of claim 67 wherein the instructions executable by the switch to identify the public virtual IP address that is mapped to the private virtual IP address include instructions executable by the switch to:

identify, by the switch, the public virtual IP address from mapping information externally received by the site switch .

71. A network device, comprising:

a switch configurable with a private virtual IP address, the switch being adapted to identify a public virtual IP address that is mapped to the private virtual IP address configured at the switch, and the switch being adapted to communicate the identified public virtual IP address to a load balancing controller.

72. The network device of claim 71 wherein the load balancing controller is included in the switch.

73. The network device of claim 71 wherein the switch is adapted to said identify the public virtual IP address from mapping information internally stored in the switch.

74. The network device of claim 71 wherein the switch is adapted to said identify the public virtual IP address from mapping information externally received by the site switch.