How Targets of an Operator are Processed › Processing a Target Specified as an IP Address or FQDN

Processing a Target Specified as an IP Address or FQDN

When you use an IP address or FQDN to specify the target host of an operator, CA Process Automation repeatedly queries the Domain Name Server (DNS). If you specify an FQDN as the target, the first search returns the IP addresses defined on the host with that FQDN. If you specify an IP address, the first search returns the host FQDN and IP addresses associated with that FQDN. Each subsequent search tests against all of the host specifiers that are retrieved in the initial search.

CA Process Automation looks for all of the ways that the target host is configured in the current CA Process Automation environment. A host group defines remote hosts with subnet and host name patterns. Therefore, a host group can include hosts with Orchestrators or agents that are mapped to touchpoints. A host group can also include individual hosts that are mapped to a proxy touchpoint. A host that is identified with an IP address or FQDN could be processed with a touchpoint name or proxy touchpoint name.

Some searches find any active Orchestrators or agents that are defined on the host that have enabled touchpoints. Another search finds any enabled proxy touchpoint on an active agent that is mapped to the host. A search finds enabled host groups on an active agent with host name patterns or IP address subnets that match the FQDN or IP address. When search criteria are met, these queries delay the start of the operator run. CA Process Automation runs the operator on the first found enabled touchpoint, proxy touchpoint, or host group that is running on an active Orchestrator or agent. The touchpoint, proxy touchpoint, or host group must belong to the current environment. When none of the search criteria are met, the operator fails and an error message is generated.

The Target area of the Execution Settings tab for operators contains a "Match target in Host Groups only" check box. Select this check box in the following cases:

• When specifying an IP address within a subnet that is specified in a host group.
• When specifying a host name that matches a pattern that is specified in a host group.

When you select the Look Up DNS Check box, CA Process Automation resolves the target name by doing a lookup in DNS. The lookup is for a record that matches a reference by a host group.

Consider the case where you clear this check box but the target IP address or FQDN exists. The following processing determines the host on which to run the operator:

1. The application searches the DNS for all of the identifiers for the specified target. If the target is specified as an FQDN, CA Process Automation searches for all the IP addresses for that FQDN. If the target is an IP address, CA Process Automation searches for the FQDN and for other IP addresses for that FQDN.
   • If the connection to the DNS fails, the application writes an error to the log file and exits.
   • If the query returns the FQDN and other IP addresses, the application uses the specified IP address and this result set for all subsequent searches.
   • If the query returns one or more IP addresses, the application uses the specified FQDN and the IP addresses in all subsequent searches.
2. The application searches for an active Orchestrator with an enabled touchpoint (current environment) that is installed on a host in the Step 1 search results.
   • If found, the application runs the operator on that Orchestrator touchpoint.
   • If not found, the application continues processing.

     Note: The application does not detect clustered Orchestrators. Hosts with clustered Orchestrators do not appear in the domain configuration.

3. The application searches for an active agent with an enabled touchpoint (current environment) that is installed on a host in the Step 1 search results.
   • If the host has an active agent with one enabled touchpoint, CA Process Automation uses that touchpoint to run the operator.
   • If the host has an active agent with multiple enabled touchpoints, CA Process Automation uses one of the enabled touchpoints to run the operator.
   • If not found, the application continues processing.
4. The application searches for an active agent that is connected to the remote target host. This agent must have an enabled proxy touchpoint or host group in the current environment. For host groups, the queries use pattern matching. The host group queries find whether the referenced subnet or host name pattern includes a host identifier in the Step 1 result set. For proxy touchpoints, the application searches for an exact match to any of the host identifiers that are retrieved in Step 1.
   • If the only match is a remote host referenced by a proxy touchpoint, the application runs the operator on that remote host.
   • If the only match is a remote host referenced by a host group, the application runs the operator on that remote host.
   • If the application finds multiple matches, it runs the operator on the first remote host found that is referenced by either a proxy touchpoint or a host group.
   • If there are no matches to the search criteria, the application continues processing.
5. The application determines why the operator did not run. Then, the application fails the operator with a failure message.
   • Condition: None of the identifiers that are retrieved in Step 1 belongs to any host in the current environment.

     Results: The application fails the operator with the following message:

     Message could not be posted to the node.
     

   • Condition: One or more identifiers that are retrieved in Step 1 belong to a host where all Orchestrators and agents are inactive.

     Results: The operator fails with the following message:

     Message could not be posted to the node.
     

   • Condition: One or more Step 1 identifiers belong to a host with all disabled touchpoints or is referenced with only disabled proxy touchpoints or host groups.

     Results: The application returns a disabled touchpoint or host group in the TouchpointName field of the operator dataset system output variables. The application fails the operator with the following error message:

     Node is disabled.
     

Note: Consider the exception where the user specifies a host name or IP address in the Target field of an Invoke Java operator. CA Process Automation looks first for a matching agent host. If successful, the Invoke Java operator runs on the agent host. If the search fails, the application looks for a matching Orchestrator host. If found, it attempts to run but the Invoke Java operator fails because it cannot run on an Orchestrator.

More information:

Target Settings