When executing a job, Netmail Archive splits the workload of the job up into subtasks, one for each account allocated to the job. In a single archive server scenario, all of these subtasks are run on the one server, but Netmail Archive uses multi-threading to execute the job for several accounts at the same time.
Netmail Archive also allows you to configure your Netmail Archive system to support a multi-archive server clustered environment. Netmail Archive is configured to automatically detect any additional archive nodes you configure and cluster together for maximum performance and uptime. Within a cluster, the Master node is responsible for distributing job workload across all nodes of the cluster. It will automatically detect the current load of any of the Worker nodes in the cluster and distribute the job workload between nodes accordingly to better utilize system resources.
When jobs are running, you can view how they are distributed across the available nodes by using the Monitor feature. From the tree menu on the left-hand side of the Netmail Administration Console, click the Archive object. By default, the Monitor tab is displayed. The Monitor tab allows you to monitor the progress of jobs onscreen. Click the + icon next to the Cluster Node to expand the node and monitor the jobs onscreen. For more information on the Monitor tab, see Monitoring Job Progress.
To help support the multi-threading and cluster operation of jobs, several server, or node, settings need to be set. In the Netmail Administration Console under Archive > Clusters > <Cluster Name> > Nodes, use the arrow icon to expand the tree. If you have installed only a single node on your Netmail Archive system, this node will appear in the tree as the Default Master node. If you have installed more than one node, these additional nodes will appear as Worker nodes. On a Netmail Archive system, you can have many Worker nodes, but only one Master node.
To view more information about your Master or Worker nodes, click the name of the node to open it. By default, the Configuration tab is displayed. The Configuration tab allows you to change various configuration settings associated with the selected node.
During installation, Netmail Archive configures nodes with default settings, however, you can still make changes to these settings at any time if you need to modify system operation.
This setting allows you to specify how long you want Netmail Archive to wait before cancelling a job if the system encounters an error during processing, such as hanging or freezing. To change the default Time out value, set the time out value, in seconds, to indicate how long you want Netmail Archive to wait before cancelling a job, and then click Save.
This option allows you to specify a temporary directory where attachments are stored during job processing. These attachments are cleaned up after the job finishes processing. To change the default Temporary directory, edit the path, and then click Save. When large accounts are being processed, the number of cached attachments can be quite large. As such, you should ensure that the specified location has adequate free space. Use the Test button to ensure that the path is accessible.
This option displays the maximum number of job threads that are processed at the same time by this node. Note that this is the maximum number for the node, not per job. It is possible to run multiple jobs concurrently, but the Maximum threads setting will restrict the number of threads which can run across all jobs on this node. To change the default number of maximum threads, edit the value, and then click Save.
Note: Netmail recommends that you leave the default value at 10 threads. However, if you consistently see that CPU utilization on the node is maxed out or well underutilized during job execution, you can increase or decrease this setting accordingly.
This option allows you to control which jobs or job types will be eligible for execution on this node. To include all agents for processing by this node, select the All the agents option under Inclusion. Otherwise, click Edit to select specific agents or jobs. If you want to exclude specific jobs or job types from executing on this node, click Edit next to Exclusion, and select the agents you want to exclude.
It is the Master node which inspects the Filter settings of all the nodes when it is deciding where to allocate the accounts from a particular job. By default, all nodes, including the Master, are set to accept accounts from all job types. In some scenarios, you may wish to dedicate a specific node to execute the jobs of a particular Agent (e.g., all Export jobs). In such a scenario, you would simply exclude that Agent in the filter of all nodes except for the one on which you want them to run.
Note: If you dedicate an agent to a specific node, the dedicated node will assume the task of processing all jobs associated with that agent. In the event of a failure, jobs associated with the dedicated node will not be re-distributed among the cluster.