Load Balancing
Depending on your deployment design and the number of concurrent recorded sessions, you may need to deploy additional ObserveIT Application Servers.
For the steps required to install additional Application Server(s), see Installing ObserveIT Application Server.
When deploying more than one Application Server, you need to load balance the Agent connections with the multiple Application Servers. You may use software-based load balancing solutions, such as Microsoft Network Load Balancing (NLB), or hardware-based solutions, such as F5, Citrix NetScaler, or others.
Checking the Status of the Application Servers
A keep-alive component is required so that the load balancer can check the status of the ObserveIT Application Servers.
The probe URL for the Application Server keep-alive is:
If using HTTP:
http://{App_Server_FQDN}:4884/ObserveitApplicationServer/v2/apis/health/_health
4884 is the default port, it can be changed through IIS, and if needed SSL can also be enabled (which usually changes the port to 443).
If using HTTPS:
https://{App_Server_FQDN}/ObserveitApplicationServer/v2/apis/health/_health
Expected reply: 200
For example:
{"_status":{"status":200,"code":"it:error:none","context":{"transactionId":"","correlationId":""}},"_meta":{"origin":{},"stats":{}},"status":"Healthy","database":{"status":"Healthy","roundTripTime":"00:00:00.0017518"},"fileSystem":{"status":"Healthy","roundTripTime":"00:00:00.0033923"}}
You can change the health check interval to 10 seconds by editing the HealthCheckSecondsInterval value in the web.config file on the Application Server(s).
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