Solace Message VPN Replications Test

Replication uses corresponding Message VPNs with active and standby replication states at separate replication sites to ensure that Guaranteed Messaging clients can continue to have service through a specified Message VPN should one data center become unavailable. When replication is enabled, Guaranteed messages received by durable endpoints in a Message VPN with an active replication state at one replication site are automatically propagated to corresponding durable endpoints in a duplicate Message VPN with a standby replication state at the other replication site. In addition, local and XA transactions that publish or consume replicated Guaranteed messages are automatically propagated to the standby replication site. If a service failover to one replication site occurs, clients can reconnect to the same Message VPN at a different replication site to continue to receive service, and any messages that were received, but not consumed, before the service interruption can be delivered to them.

The success of any replication system rests on how quickly the Message VPNs in a standby replication site reconnect with the primary Message VPN after a failure, and how rapidly data synchronization occurs between the Message VPNs. If Message VPNs on the replication site take too long to reconnect with the primary Message VPN after losing contact, or if there are too many messages that are queued on the primary Message VPN to be sent to the standby Message VPN in a replication site, then the replication process will be sluggish. To avoid this, administrators should continuously monitor the replication process on the Message VPNs, proactively identify pain points, and promptly initiate measures to eliminate them, so that the data on the Message VPNs across primary and standby replication sites are in-sync at all times. This is where the Solace Message VPN Replications test helps!

This test auto-discovers the Message VPNs configured on the target broker and first determines whether/not replication is enabled on each Message VPN. When each Message VPN is in an active state on the replication site, then, the test reports the number of synchronous and asynchronous messages that were queued to the standby/backup Message VPN on the replication site and the count of messages that were transmitted to the stanby/backup replication site. If the Message VPN is on standby, then, the test reveals the count of transaction replication requests received by each Message VPN. Transaction replication request failures noticed on the each Message VPN alerts administrators to potential problems which needs immediate attention / resolution. With the help of these metrics, administrators can quickly spot anomalies in the replication process and initiate measures to resolve them.

Target of the test : A Solace PubSub+ Event Broker

Agent deploying the test : A remote agent

Outputs of the test : One set of results for each Message VPN configured on the target Solace PubSub+ Event Broker being monitored

Configurable parameters for the test
Parameter Description

Test Period

How often should the test be executed.

Host

The IP address of the target host for which this test is to be configured.

Port

Refers to the port at which the Solace PubSub+ Event Broker listens to.

UserName and Password

By default, the eG agent executes SEMP ( Solace Element Management Protocol) APIs on the target broker to collect the required metrics. For the eG agent to execute the SEMP APIs, a special user with read only privilege is required. Specify the credentials of such a user in the UserName and Password text boxes. To know how to create such a user, refer to Creating a New User for Monitoring Solace PubSub+ Event Broker.

Confirm Password

Confirm the Password by retyping it in the Confirm Password text box.

SSL

By default, this flag is set to No indicating that the Solace PubSub+ Event Broker is not SSL-enabled by default. Set this flag to Yes if the Solace PubSub+ Event Broker is SSL-enabled.

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

Replication role

Indicates the replication role configured for this Message VPN.

 

The values reported by this measure and its numeric equivalents are mentioned in the table below:

Measure values Numeric values
Active 1
Standby 0

Note:

By default, this measure reports the Measure Values listed in the table above to indicate the replication role configured for each Message VPN. The graph of this measure however, is represented using the numeric equivalents only i.e., 0 or 1.

Replication enabled

Indicates the replication administrative status of this Message VPN.

 

The values reported by this measure and its numeric equivalents are mentioned in the table below:

Measure values Numeric values
Enabled 1
Shutdown 0

Note:

By default, this measure reports the Measure Values listed in the table above to indicate the administrative status of each Message VPN. The graph of this measure however, is represented using the numeric equivalents only i.e., 0 or 1.

Transaction replication mode

Indicates the mode using which this Message VPN replicates transactions.

 

The values reported by this measure and its numeric equivalents are mentioned in the table below:

Measure values Numeric values
Sync 1
Async 0

Note:

By default, this measure reports the Measure Values listed in the table above to indicate the mode using which each Message VPN replicates transactions. The graph of this measure however, is represented using the numeric equivalents only i.e., 0 or 1.

Reject ineligible sync messages

Indicates whether/not reject-msg-when-sync-ineligible option is enabled for this Message VPN.

 

If the risks associated with asynchronous replication are not acceptable, it is possible to ensure synchronous replication is always strictly enforced. To maintain a synchronous replication mode, you can enable the reject-msg-when-sync-ineligible option for a Message VPN. With this enabled, synchronous replicated messages or transactions are rejected if they cannot be successfully stored on both the active and standby site.

The values reported by this measure and its numeric equivalents are mentioned in the table below:

Measure values Numeric values
Yes 1
No 0

Note:

By default, this measure reports the Measure Values listed in the table above to indicate whether/not reject-msg-when-sync-ineligible option is enabled for each Message VPN. The graph of this measure however, is represented using the numeric equivalents only i.e., 0 or 1.

Connection retry delay

Indicates the time delay noticed on this Message VPN during connection retry.

Seconds

Compare the value of this measure across Message VPNs to identify the Message VPN on which maximum time delay was noticed during connection retry.

TLS enabled

Indicates whether/not SSL encryption is enabled on this Message VPN.

 

The values reported by this measure and its numeric equivalents are mentioned in the table below:

Measure values Numeric values
Yes 1
No 0

Note:

By default, this measure reports the Measure Values listed in the table above to indicate whether/not SSL encryption is enabled on each Message VPN. The graph of this measure however, is represented using the numeric equivalents only i.e., 0 or 1.

Compression

Indicates whether/not compression is enabled on this Message VPN.

 

The values reported by this measure and its numeric equivalents are mentioned in the table below:

Measure values Numeric values
Yes 1
No 0

Note:

By default, this measure reports the Measure Values listed in the table above to indicate whether/not compression is enabled on each Message VPN. The graph of this measure however, is represented using the numeric equivalents only i.e., 0 or 1.

Queue quota

Indicates the quota allocated for queue on this Message VPN.

MB

 

Reject messages to sender on discard

Indicates whether/not the reject-msg-to-sender-on-discard option is enabled for queue on this Message VPN.

 

The reject-msg-to-sender-on-discard option configures how a durable queue should handle ingress messages discards that occur due to one or more of the following conditions:

  • adding the published message will exceed the configured message quota for the queue

  • the published message exceeds the maximum message size allowed for the queue

  • the client published the message to a topic it has also subscribed to and has an active flow with "No Local Delivery"

The values reported by this measure and its numeric equivalents are mentioned in the table below:

Measure values Numeric values
Yes 1
No 0

Note:

By default, this measure reports the Measure Values listed in the table above to indicate whether/not the reject-msg-to-sender-on-discard option is enabled for queue on each Message VPN. The graph of this measure however, is represented using the numeric equivalents only i.e., 0 or 1.

Mate flow congested high watermark

Indicates the maximum time taken by this Message VPN to store messages when the message VPN experienced a sudden large influx of messages i.e., during message flow congestion.

 

By default, this measure is displayed in the Month:Days:Hours:Mins:Secs format.Compare the value of this measure across Message VPNs to identify the Message VPN that is taking maximum time to store messages during message flow congestion.

Mate flow not congested high watermark

Indicates the maximum time taken by this Message VPN to store messages.

 

By default, this measure is displayed in the Month:Days:Hours:Mins:Secs format.

Compare the value of this measure across Message VPNs to identify the Message VPN that is taking maximum time to store messages.

Eligible high watermark

Indicates the maximum time taken by this Message VPN to store messages that are eligible for synchronous replication.

 

By default, this measure is displayed in the Month:Days:Hours:Mins:Secs format.

Ineligible high watermark

Indicates the maximum time taken by this Message VPN to store messages that are ineligible for synchronous replication.

 

By default, this measure is displayed in the Month:Days:Hours:Mins:Secs format.

Async messages queued to standby

Indicates the number of asynchronous messages that were queued from this Message VPN to standby Message VPN.

Number

Compare the value of this measure across Message VPNs to identify the Message VPN from which maximum number of asynchronous messages were queued to standby Message VPN.

Promoted messages queued to standby

ndicates the number of promoted messages that were queued to the standby Message VPN from this Message VPN.

Number

Compare the value of this measure across Message VPNs to identify the Message VPN from which maximum number of promoted messages were queued to standby Message VPN.

Locally consumed messages

Indicates the number of messages that were pruned by this Message VPN during the last measurement period.

Number

 

Sync messages queued to standby

Indicates the number of synchronous messages that were queued to the standby Message VPN from this Message VPN.

Number

Compare the value of this measure across Message VPNs to identify the Message VPN from which maximum number of synchronous messages were queued to standby Message VPN.

Sync messages queued to standby as async

Indicates the number of synchronous messages that were queued to the standby Message VPN as asynchronous messages from this Message VPN.

Number

Compare the value of this measure across Message VPNs to identify the Message VPN from which maximum number of synchronous messages were queued to standby Message VPN as asynchronous messages.

ACKs propagated to standby

Indicates the number of acknowledgment messages that were propagated from this Message VPN to the standby Message VPN during the last measurement period.

Number

 

Reconcile requests from standby

Indicates the number of reconcile requests received by this Message VPN from a standby Message VPN during the last measurement period.

Number

 

Transaction replications requests

Indicates the total number of transaction replication requests received by this Message VPN while in standby mode during the last measurement period.

Number

Compare the value of this measure across Message VPNs to identify the Message VPN that received maximum number of transaction replication requests while in standby mode.

Total transaction replications success

Indicates the total number of transaction replication requests that were successful when this Message VPN was in standby mode during the last measurement period.

Number

Compare the value of this measure across Message VPNs to identify the Message VPN on which maximum number of transaction replication requests were successful when the Message VPN was in standby mode.

Transaction replications commit success

Indicates the number of transaction replication requests that were committed successfully when this Message VPN was in standby mode during the last measurement period.

Number

Compare the value of this measure across Message VPNs to identify the Message VPN on which maximum number of transaction replication requests were committed successfully when the Message VPN was in standby mode.

Transaction replications prepare success

Indicates the number of transaction replication requests that were prepared successfully when this Message VPN was in standby mode during the last measurement period.

Number

Compare the value of this measure across Message VPNs to identify the Message VPN on which maximum number of transaction replication requests were prepared successfully when the Message VPN was in standby mode.

Transaction replications rollback success

Indicates the number of transaction replication requests that were rolled back successfully when this Message VPN was in standby mode during the last measurement period.

Number

Compare the value of this measure across Message VPNs to identify the Message VPN on which maximum number of transaction replication requests were rolled back successfully when the Message VPN was in standby mode.

Total transaction replications failed

Indicates the total number of transaction replication requests that failed when this Message VPN was in standby mode during the last measurement period.

Number

Ideally, the value of this measure should be 0.

Compare the value of this measure across Message VPNs to identify the Message VPN that encountered maximum number of transaction replication failures when the Message VPN was in standby mode.

Transaction replications commit failed

Indicates the number of transaction replication requests that failed commits when this Message VPN was in standby mode during the last measurement period.

Number

Ideally, the value of this measure should be 0.

Compare the value of this measure with Transaction replications prepare failed and Transaction replications rollback failed measures to identify the type of transaction replication request failure that was frequently encountered by each Message VPN while the Message VPN was in standby mode.

Transaction replications prepare failed

Indicates the number of transaction replication requests that failed to be prepared when this Message VPN was in standby mode during the last measurement period.

Number

Compare the value of this measure with Transaction replications commit failed and Transaction replications rollback failed measures to identify the type of transaction replication request failure that was frequently encountered by each Message VPN while the Message VPN was in standby mode.

Transaction replications rollback failed

Indicates the number of transaction replication requests that failed rollback when this Message VPN was in standby mode during the last measurement period.

Number

Compare the value of this measure with Transaction replications commit failed and Transaction replications prepare failed measures to identify the type of transaction replication request failure that was frequently encountered by each Message VPN while the Message VPN was in standby mode.

Messages received from active

Indicates the total number of messages that were received when this Message VPN was in standby mode during the last measurement period.

Number

 

Acks received from active

Indicates the number of acknowledgment propagation messages that were received when this Message VPN was in standby mode during the last measurement period.

Number

 

Out of sequence ACKs received

Indicates the number of out of sequence acknowledgments received when this Message VPN was in standby mode during the last measurement period.

Number

 

Reconcile requests sent to active

Indicates the number of reconcile requests sent to the active Message VPN when this Message VPN was in standby mode during the last measurement period.

Number

 

Transitions to sync ineligible

Indicates the number of times this Message VPN transitioned to ineligible state to receive messages from a particular topic or queue.

Number

A Message VPN could transition to ineligible state due to various reasons such as network connectivity issues, subscription lag, flow control issues or WAN bandwidth issues that need to be addressed by the system administrator.

Total replicated topics

Indicates the total number of topics that were replicated through this Message VPN.

Number

The detailed diagnosis of this measure lists the name of the topic and replication mode.