What Happens When an Agent Connection Request is Denied

Based on the configurations that are set in loadbalancing.xml and the introscope.apm.agentcontrol.agent.allowed property, agents are allowed or disallowed connection to specific Enterprise Managers. When an agent requests a connection to an Enterprise Manager, the Enterprise Manager can accept or deny the connection request.
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Based on the configurations that are set in loadbalancing.xml and the introscope.apm.agentcontrol.agent.allowed property, agents are allowed or disallowed connection to specific Enterprise Managers. When an agent requests a connection to an Enterprise Manager, the Enterprise Manager can accept or deny the connection request.
Agents are denied connection when any of the following take place:
  • The introscope.apm.agentcontrol.agent.allowed property is set to true and loadbalancing.xml disallows the agent.
  • The introscope.apm.agentcontrol.agent.allowed property is set to false and loadbalancing.xml does not explicitly allow the agent.
  • One of these clamp values is reached or exceeded:
    • introscope.enterprisemanager.agent.disallowed.connection.limit.
    • introscope.enterprisemanager.agent.connection.limit.
When an Enterprise Manager denies an agent connection request, these actions can take place:
  • An agent that is connected to an Enterprise Manager disconnects.
  • A disconnected agent tries to connect to other Enterprise Mangers to which it is allowed to connect.
The agent keeps trying Enterprise Managers until it can either connect or it runs out of Enterprise Managers:
  • To which the agent is allowed to connect.
  • Available for connection.
If an agent is denied on all Enterprise Managers, then how the agent acts differs based on its introscopeagent.profile file introscope.agent.enterprisemanager.failbackRetryIntervalInSecondsproperty setting. If the property configuration is set as follows:
  • Uncommented and a time duration set, then the agent keeps trying to connect to allowed Enterprise Managers periodically based on the duration.
  • Not set (commented out), then based on the CA APM agent version agents act as follows:
    • Valid for pre-9.1 agent:
      Disconnects from the Enterprise Manager and keeps trying to reconnect.
    • Valid for 9.1 and later agent:
      Passively connects to the final allowed Enterprise Manager in its Allowed Enterprise Manager list. The agent does not send any metric data to the Enterprise Manager. The agent is dormant as it waits for the Enterprise Manager configuration information to change the agent to an allowed state.