Systems and Methods for GSLB Based on SSL VPN Users

• US 20100131960A1
• Filed: 11/25/2008
• Published: 05/27/2010
• Est. Priority Date: 11/25/2008
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: RAJA, Murali, Kamath, Sandeep, SUGANTHI, Josephine
• Granted Patent: US 8,639,813 B2
• Time in Patent Office: Days
• US Class Current: 718/105
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 63/0227 Filtering policies mail message filtering H04L51/212
• CPC Class Codes: H04L 63/0272 Virtual private networks
• CPC Class Codes: H04L 63/1433 Vulnerability analysis
• CPC Class Codes: H04L 63/166 at the transport layer
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30

Abstract

The present invention provides a system and a method for global server load balancing of a plurality of sites based on a number of Secure Socket Layer Virtual Private Network (SSL VPN) users. The SSL VPN users may access servers at each of the plurality of sites. A global server load balancing virtual server (GSLB) may receive a request to access a server. The GSLB virtual server may load balance a plurality of sites wherein each of the plurality of sites may further comprising a load balancing virtual server load balancing users accessing the server accessing servers via an SSL VPN session. GSLB may receive from a first load balancing virtual server at a first site, a first number of current SSL VPN users accessing servers from the first site via SSL VPN sessions. The GSLB may also receive from a second load balancing virtual server at a second site, a second number of current SSL VPN users of the users accessing servers from the second site via SSL VPN sessions. GSLB may determine to forward the request to one of the first load balancing virtual server of the first site or the second load balancing virtual server of the second site by load balancing SSL VPN users across the plurality of sites based on the first number of current SSL VPN users and the second number of current SSL VPN users.

Claims

1. A method for global server load balancing a plurality of sites based on a number of Secure Socket Layer Virtual Private Network (SSL VPN) users accessing servers at each of the plurality of sites, the method comprising:

a) receiving, by a global server load balancing (GSLB) virtual server, a request to access a server, the GSLB virtual server load balancing a plurality of sites, each of the plurality of sites comprising a load balancing virtual server load balancing users access to servers, a plurality of the users accessing servers via an SSL VPN session;

b) receiving, by the GSLB virtual server from a first load balancing virtual server at a first site, a first number of SSL VPN users accessing servers from the first site via SSL VPN sessions;

c) receiving, by the GSLB virtual server from a second load balancing virtual server at a second site, a second number of SSL VPN users accessing servers from the second site via SSL VPN sessions; and

d) determining, by the GSLB virtual server, to forward the request to one of the first load balancing virtual server of the first site or the second load balancing virtual server of the second site by load balancing SSL VPN users across the plurality of sites based on the first number of SSL VPN users and the second number of current SSL VPN users.

2. The method of claim 1, wherein step (a) further comprises receiving, by the GSLB virtual server of a first appliance, the request to access the server vi an SSL VPN session.

3. The method of claim 1, wherein step (b) further comprises determining, by the first load balancing virtual server of a second appliance, the first number of SSL VPN users accessing servers via the second appliance and wherein step (c) further comprises determining, by the second load balancing virtual server of a third appliance, the second number of SSL VPN users access servers via the third appliance.

4. The method of claim 1, wherein step (b) further comprises requesting, by the GSLB virtual server, a number of SSL VPN users from the first load balancing virtual server via an SNMP (Simple Network Management Protocol) request, the number of SSL VPN users identified via an object identifier, the first load balancing virtual server updating a value of an object identified by the object identifier.

5. The method of claim 1, wherein step (b) further comprises receiving, by the GSLB virtual server of a first appliance, the first number of SSL VPN users from the first load balancing virtual server of a second appliance via a metric exchange protocol communicated between the first appliance and the second appliance.

6. The method of claim 1, wherein step (c) further comprises requesting, by the GSLB virtual server, a number of SSL VPN users from the second load balancing virtual server via an SNMP (Simple Network Management Protocol) request, the number of SSL VPN users identified via an object identifier, the second load balancing virtual server updating a value of an object identified by the object identifier.

7. The method of claim 1, further comprising determining by the first virtual load balancer of a first appliance the first number of SSL VPN users from all users accessing the first site via the first appliance and determining by the second virtual load balancer of a second appliance the first number of SSL VPN users from all users accessing the second site via the second appliance

8. The method of claim 1, wherein step (d) further comprises determining, by the GSLB virtual server, a threshold of a maximum number of SSL VPN users for the first site has been reached and responsive to the determination, forwarding the request to the second site.

9. The method of claim 1, wherein step (d) further comprises determining, by the GSLB virtual server, a threshold of a maximum number of SSL VPN users for the second as been reached and responsive to the determination, forwarding the request to the first

10. The method of claim 1, wherein step (d) further comprises determining, by the GSLB virtual server, to forward the request to one of the first load balancing virtual server of the first site or the second load balancing virtual server of the second site by load balancing SSL VPN users across the plurality of sites in combination with any of the following load balancing methods:

least connection, least response time, least bandwidth, least packets and round trip time.

11. A system for global server load balancing a plurality of sites based on a number of Secure Socket Layer Virtual Private Network (SSL VPN) users accessing servers at each of the plurality of sites, the method comprising:

a global server load balancing (GSLB) virtual server of a first appliance receiving a request to access a server, the GSLB virtual server load balancing a plurality of sites, each of the plurality of sites comprising a load balancing virtual server load balancing users access to servers, a plurality of the users accessing servers via an SSL VPN session;

a first load balancing virtual server of a second appliance at a first site providing to the GSLB virtual server a first number of SSL VPN users accessing servers from the first site via SSL VPN sessions;

a second load balancing virtual server at a second site of a third appliance providing to the GSLB virtual server a second number of SSL VPN users accessing servers from the second site via SSL VPN sessions; and

wherein the GSLB virtual server determines to forward the request to one of the first load balancing virtual server of the first site or the second load balancing virtual server of the second site by load balancing SSL VPN users across the plurality of sites based on the first number of SSL VPN users and the second number of SSL VPN users.

12. The system of claim 11, wherein the GSLB virtual server of the first appliance receives the request to access the server vi an SSL VPN session.

13. The system of claim 11, wherein the first load balancing virtual server of the second appliance determine the first number of SSL VPN users accessing servers via the second appliance and the second load balancing virtual server of the third appliance determines the second number of SSL VPN users access servers via the third appliance.

14. The system of claim 11, wherein the GSLB virtual server of the first appliance requests a number of SSL VPN users from the first load balancing virtual server via an SNMP (Simple Network Management Protocol) request, the number of SSL VPN users identified via an object identifier, the first load balancing virtual server updating a value of an object identified by the object identifier.

15. The system of claim 11, wherein the GSLB virtual server of the first appliance receives the first number of SSL VPN users from the first load balancing virtual server of the second appliance via a metric exchange protocol communicated between the first appliance and the second appliance.

16. The system of claim 11, wherein the GSLB virtual server of the first appliance receives a number of SSL VPN users from the second load balancing virtual server of the third appliance via an SNMP (Simple Network Management Protocol) request, the number of SSL VPN users identified via an object identifier, the second load balancing virtual server updating a value of an object identified by the object identifier.

17. The system of claim 11, wherein the first virtual load balancer of the second appliance determines the first number of SSL VPN users from all users accessing the first site via the second appliance and the second virtual load balancer of the third appliance determines the second number of SSL VPN users from all users accessing the second site via the third appliance

18. The system of claim 11, wherein the GSLB virtual server determines a threshold of a maximum number of SSL VPN users for the first site has been reached and responsive to the determination, forwards the request to the second site.

19. The system of claim 11, wherein the GSLB virtual server determines a threshold of a maximum number of SSL VPN users for the second site has been reached and responsive to the determination, forwards the request to the first site.

20. The system of claim 11, wherein the GSLB virtual server determines to forward the request to one of the first load balancing virtual server of the first site or the second load balancing virtual server of the second site by load balancing SSL VPN users across the plurality of sites in combination with any of the following load balancing methods:

least connection, least response time, least bandwidth, least packets and round trip time.