Citrix Systems, Inc.

Raja, Murali

Murali Raja

Sandeep Kamath

Josephine Suganthi

Anil N Shetty

Ravi Kondamuru

Sergey Verzunov

Raghav Somanahalli Narayana

Devesh Prakash

Saravana Annamalaisami

Rishi Kaundinya Mutnuru

Abhishek Chauhan

Manikam Muthiah

Sudheer Thokala

Sridhar Srinivasan

Ranveer Kunal

Somanahalli Narayana Raghav

The present invention is directed towards systems and methods for managing a rate of request for an object transmitted between a server and one or more clients via a multi-core intermediary device. A first core of the intermediary device can receive a request for an object and assume ownership of the object. The first core can store the object in shared memory along with a rate-related counter for the object and generate a hash to the object and counter. Other cores can obtain the hash from the first core and access the object and counter in shared memory. Policy engines and throttlers in operation on each core can control the rate of access to the stored object.

Systems and methods for object rate limiting in multi-core system

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.

Systems and methods for GSLB based on SSL VPN users

The present disclosure presents systems and methods for obtaining metric information by a multi-core GSLB intermediary device and providing global server load balancing services using the obtained information. A first core of a multi-core GSLB appliance establishes a transport layer connection to a remote load balancer at a site of a plurality of sites. The first core transmits a message to each of the other cores of the multi-core GSLB appliance that the first core is a master core for receiving metric information from the load balancer. The first core receives metric information of the remote site from the load balancer. The first core propagates the metric information to each of the other cores of the GSLB appliance. A GSLB virtual server on a slave core receives a DNS request. The GSLB virtual server determines a DNS resolution for the DNS request based on the metric information.

Systems and methods for GSLB MEP connection management across multiple core appliances

A centralized configuration of a Global Server Load Balancing (GSLB) site hierarchy may be batched across a plurality of appliances in a multi-site deployment. A single GSLB site hierarchy configuration may be distributed and operated on each appliance at each site. This reduces the configuration maintained for the multi-site deployment. Furthermore, in this manner, each appliance across multiple sites has an understanding of the entire topology of the multi-site deployment. Responsive to this configuration and understanding, each appliance may perform and optimize operations according to the site topology. For example, the appliances may selectively determine which sites to establish connections with in order to share metrics. In another example, appliances may select which remote sites to monitor services according to the topology.

Systems and methods for batchable hierarchical configuration

The present invention is directed towards systems and methods for aggregating and providing statistics from cores of a multi-core system intermediary between one or more clients and servers. The system may maintain in shared memory a global device number for each core of the multi-core system. The system may provide a thread for each core of the multi-core system to gather data from the corresponding core. A first thread may generate aggregated statistics from a corresponding core by parsing the gathered data from the corresponding core. The first thread may transfer the generated statistics to a statistics log according to a schedule. The system may adaptively reschedule the transfer by monitoring the operation of each computing thread. Responsive to a request from a client, an agent of the client may obtain statistics from the statistics log.

Systems and methods for scalable N-core stats aggregation

The present application is related methods to monitor a state of one or more components of a remote access server farm by an intermediary to distinguish between operating and functional components and improve farm availability for user application requests. The intermediary may be deployed between a client and the remote access server farm and forwards client requests to functional components of the remote access server farm.

Systems and methods for monitoring components of a remote access server farm

The present invention provides methods and systems for performing load balancing via a plurality of virtual servers upon a failover using metrics from a backup virtual server. The methods and systems described herein provide systems and methods for an appliance detecting that a first virtual server of a plurality of virtual servers having one or more backup virtual servers load balanced by an appliance is not available, identifying at least a first backup virtual server of a one or more backup virtual servers of the first virtual server is available, maintaining a status of the first virtual server as available in response to the identification, obtaining one or more metrics from the first backup virtual server of a one or more backup virtual servers, and determining the load across the plurality of virtual servers using the metrics obtained from the first backup virtual server associated with the first virtual server.

Systems and methods for load balancing via a plurality of virtual servers upon failover using metrics from a backup virtual server

The present disclosure is directed towards systems and methods for global server load balancing spillover. An intermediary device providing global server load balancing (GSLB) identifies a spillover threshold for a first GSLB virtual server of the intermediary device. The first GSLB virtual server resolving DNS requests to a remote site of a plurality of remote sites. The intermediary device monitors spillover related statistics of each of a plurality of services at the plurality of remote sites, establishes a first spillover aggregate statistic for the plurality of services, determines that the first spillover aggregate statistic exceeds the spillover threshold for the first GSLB virtual server, and receives a DNS request and directing the DNS request to a second GSLB virtual server of the intermediary device responsive to the determination.

Systems and methods for GSLB spillover

Systems and methods for consolidating metrics and statistics used for load balancing by a plurality of cores of a multi-core intermediary are disclosed. A timer operating on each packet engine of each core in a multi-core system may expire. A consolidator may store, responsive to expiration of the timer, a set of counter values from each of the packet engines to a first storage location. The consolidator may send to each packet engine a message to update the set of counter values. The consolidator may, upon completion of updating the set of counter values by the packet engines, send a second message to the packet engines that includes a consolidated set of counter values determined based on the updated set of values from each packet engine. Each packet engine may establish settings and parameters for load balancing based on the consolidated set of counter values.

Systems and methods for statistics exchange between cores for load balancing

The present invention provides maintains site persistence in a hierarchical Global Server Load Balancing (GSLB) deployment. Via configuration of GSLB services locally and remotely on each of the GSLB appliances and LB appliances at a site, a site appliance identifies and associates requests from the GSLB with the site. Furthermore, the site appliance may receive a GSLB cookie with the client request and confirms the request is from the expected GSLB in the site hierarchy. When the load balancers receives a response from a server, the appliance may include the GSLB cookie with the response back to the client. The appliance may also include an LB cookie to identify the server selected by the LB. When the client sends another request, the request may include the GSLB and LB cookie.

Systems and methods for GSLB site persistence

Described herein are systems and methods for aggregating performance data or trace data for a multi-core, multi-packet-engine networked appliance. A plurality of packet engines operate on the appliance and manage network traffic between a plurality of clients and a plurality of servers. In various embodiments, the system comprises a plurality of packet engines and an aggregator communicating with the packet engines through shared memory allocations. Each packet engine can write performance data or trace data to the a shared memory allocation. The aggregator can obtain the performance data or trace data and consolidate the data to provide unified performance data or unified trace data representative of the appliance.

Systems and methods for n-core statistics aggregation

The present invention provides improvements to load balancing by providing a load balancing solution that distributes a load among a plurality of heterogenous devices, such as different types of local load balancers, using metrics collected from the different devices. The load balancing appliance collects metrics from heterogenous devices using a network management protocol and communication model, such as a Simple Network Management Protocol (SNMP). These heterogenous device metrics are available on the load balancing appliance with appliance determined metrics and metrics obtained by the appliance from homogenous devices using a metric exchange protocol. Via a configuration interface of the appliance, a user can select one or more of these different metrics for global load balancing. As such, the load balancing appliance described herein obtains a multitude of metrics from the different devices under management. Additionally, the load balancing appliance described herein provides great flexibility in allowing the user to configure the global load balancer based on the user's understanding of these multitudes of metrics and to take into account the different characteristics and behaviors of the heterogenous devices.

Systems and methods for providing global server load balancing of heterogeneous devices

Described are methods and systems for managing the connections between a client, an intermediary appliance and a server, so that asynchronous messages can be transmitted over HTTP from the server to a client. When a connection is established between a client and an intermediary, and the intermediary and a server to establish a logical client-server connection, that logical client-server connection is labeled and not maintained, while the connection between the client and the intermediary is maintained. Messages generated by the server and destined for the client are transmitted to the intermediary along with the connection label. The intermediary can then use the connection label to determine which client should receive the message.

Growing community of inventors

Santa Clara, CA, United States of America

Murali Raja