AWS DynamoDB Replication Test

Amazon DynamoDB now supports cross-region replication, a new feature that automatically replicates DynamoDB tables across AWS regions. You can use cross-region replication to build globally distributed applications with lower-latency data access, better traffic management, easier disaster recovery, and easier data migration. If a single AWS Region becomes isolated or degraded, your application can redirect to a different region and perform reads and writes against a different replica table. That is, global tables automatically promote the secondary area to become the primary region if the first region becomes unavailable. When the newly promoted primary region comes back up after a failover, updates performed in the secondary region are synchronized. However, continuous unavailability of any AWS regions can cause replication latency, which when left unattended leads to throttling and loss of critical data. This is why it is imperative to monitor the number of available and unavailable regions in the target AWS DynamoDB server.

This test monitors the target server and reports whether or not replication is enabled on the server. In addition, this test also reports the number of available and unavailable regions on the target server. This way, administrators can proactively detect the details of unavailable regions before it leads to any catastrophic outcomes.

Target of the test : An AWS DynamoDB server

Agent deploying the test :A remote agent

Outputs of the test : One set of results for the target AWS DynamoDB server being monitored.

Configurable parameters for the test

Parameter	Description
Test Period	How often should the test be executed.
Host	The IP address of the AWS DynamoDB server that is being monitored.
AWS Region	This test uses AWS SDK to interact with AWS DynamoDB and pull relevant metrics. To enable the test to connect to AWS, you need to configure the test with the name of the region to which all requests for metrics should be routed, by default. Specify the name of this AWS Region in this text box.
AWS Access Key ID, AWS Secret Access Key and Confirm Password	To monitor AWS DynamoDB, the eG agent has to be configured with the access key and secret key of a user with a valid AWS account. For this purpose, we recommend that you create a special user on the AWS cloud, obtain the access and secret keys of this user, and configure this test with these keys. The procedure for this has been detailed in the Obtaining an Access key and Secret key topic. Make sure you reconfirm the access and secret keys you provide here by retyping it in the corresponding Confirm Password text box.
Timeout Seconds	Specify the maximum duration (in seconds) for which the test will wait for a response from the server. The default is 120 seconds.
Detailed Diagnosis	To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option. The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled: The eG manager license should allow the detailed diagnosis capability Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.

Measurements made by the test

Measurement	Description	Measurement Unit	Interpretation
Is replication enabled?	Indicates whether/not replication is enabled on the target server.		The values reported by this measure and its numeric equivalents are mentioned in the table below: Measure values Numeric values Yes 100 No 0 Note: By default, this measure reports the Measure Values listed in the table above to indicate whether or not replication is enabled. The graph of this measure however, is represented using the numeric equivalents only i.e., 0 or 100.
Replication region available	Indicates the number of replication regions that are currently available.	Number	Use the detailed diagnosis of this measure to find out the name of the available regions.
Replication region unavailable	Indicates the number of replication regions that are not available.	Number	The detailed diagnosis of this measure list outs the names of the unavailable regions.