AWS Elastic Load Balancing Idle Connection Timeout Impact over application connecting to ScaleArc?

"Elastic Load Balancing automatically distributes incoming application traffic across multiple Amazon EC2 instance in the cloud.  It enables you to achieve greater levels of fault tolerance in your applications, seamlessly providing the required amount of load balancing capacity needed to distribute application traffic." 

In configuring Active/Active or Active/Passive ScaleArc on AWS, it requires an ELB to be configured to load balance the traffic between the two ScaleArc systems. 

App Servers are sending traffic to ScaleArc EC2 Instance using Elastic Load Balancer. It has been observed, although ScaleArc Max idle connection Timeout setting set to 1200 seconds but still App Servers connections got timeout only in 60 seconds of inactivity observed over connection.

You can see here as we are connecting to ScaleArc Cluster using elastic load balancer IP, with more than 1 minute of inactiveness in the sesssion, connection id got changed. You may observed crash in the application and unresponsiveness beacuse of this.

To overcome the impact, It is highly advisable to change idle connection timeout setting for AWS Elastic LoadBalancer same as you configured over corresponding ScaleArc Cluster "Idle Client Connection Time" setting.

Change Idle timeout value to 1200 seconds.

If you are experiencing issues with ScaleArc or with any of it's features, please contact ScaleArc Support. We are available 24x7 by phone at 855 800 7225 or +1 408 412 7315. For general support inquiries, you can also e-mail us at support@scalearc.com.

Permalink: https://support.scalearc.com/kb/articles/4363