Configure Citrix ADM agents for multisite deployment

Agents work as an intermediary between the Citrix ADM service and the discovered instances across different data centers and public clouds. Citrix ADM supports agent failover within a data center or a public cloud.

The following are the benefits of installing agents:

  • The configured instances to an agent send the unprocessed data directly to the agent instead of Citrix ADM service. Agent does the first level of data processing and send the processed data in compressed format to the Citrix ADM for storage.

  • Agents and instances are co-located in the same data center or cloud so that the data processing is faster.

  • Clustering the agents provides redistribution of Citrix ADC instances on agent failover. When one agent in a site fails, traffic from Citrix ADC instances switches to another available agent in the same site.

Architecture

The following figure illustrates Citrix ADC instances configured on multiple agents in a data center and public cloud to achieve agent failover:

Citrix ADM agents configured for multisite deployment

The public cloud has four ADC instances and two ADM agents. The enterprise data center also have four ADC instances and two ADM agents. Each agent is configured with two ADC instances.

The agents receive data directly from the configured instances. After agent receives the data, agent processes the data and sends to the Citrix ADM service in a compressed format. Agents communicate with the Citrix ADM server over a secure channel.

On public cloud, when Citrix ADM Agent 1 becomes inactive (DOWN state), agent failover occurs. Citrix ADM service redistributes the ADC instances of Citrix ADM Agent 1 with Citrix ADM Agent 2. The instace redistribution occurs on an enterprise data center if one of the agents fail in the data center.

To install a Citrix ADM agent, see Install the Citrix ADM Agent.

Citrix ADM Agent failover

The agent failover can occur in a site that has two or more registered agents. When an agent becomes inactive (DOWN state) in the site, the Citrix ADM service redistributes the ADC instances of the inactive agent with other active agents.

Important

  • Ensure Agent Failover feature is enabled on your account. To enable the this feature, see Enable or disable ADM features.

  • If an agent is runnig a script, ensure that script is present on all the agents in the site. Therefore, the changed agent can run the script after agent failover.

To attach a site to an agent in Citrix ADM GUI:

  1. Navigate to Networks > Agents.

  2. Select an agent that you want to attach to a site.

  3. Specify the site from the list. If you wish to add a new site, click Add.

  4. Click Save.

To achieve an agent failover, select Citrix ADM agents one by one and attach to the same site.

For example, two agents 10.106.1xx.2x and 10.106.1xx.7x are attached and operational in the Bangalore site. If one agent becomes inactive, Citrix ADM detects it and displays the state as down.

When a Citrix ADM agent becomes inactive (Down state) in a site, Citrix ADM waits for five minutes for the agent to become active (Up state). If the agent continue to remain inactive, Citrix ADM automatically redistributes the instances among available agents in the same site.

Citrix ADM triggers instance redistribution every 30 minutes to balance the load among active agents in the site.

The instances attached and automatically reconfigured to agents in the same site for trap destination, syslog server, and analytics.

Configure Citrix ADM agents for multisite deployment