F5 BIG-IP LTM monitoring

Learn about F5 BIG-IP LTM Extension configuration, deployment and working with data.

Before you begin

Verify that your designated ActiveGate has the Extensions 2.0 module active and running.

1. In the Dynatrace menu, go to Deployment status > ActiveGates and expand the details of the designated ActiveGate.
2. In the Properties section, make sure that the ActiveGate is assigned to a Group.
3. In the Modules section, make sure that the Extensions 2.0 module is enabled.

If either of these properties needs to be changed, see Configuration properties and parameters of ActiveGate.

Note: Any changes done via ActiveGate configuration files require a restart of the ActiveGate and Extensions Execution Controller (EEC) services.

Extension deployment

1. In the Dynatrace menu, go to Extensions. Find the F5 BIG-IP LTM tile in the Dynatrace Extensions 2.0 you can add to your environment section.
2. Select the tile, then select Add to environment.

Monitoring configuration

1. Make sure the expected version is displayed in the Versions list at the bottom of the page.
2. Add your monitoring configuration by selecting Add monitoring configuration.

Define devices

Select Add device to define the devices from which you want to pull data and provide the device connection details:

• IP address or device name
• Port
• SNMP version and related authentication details

ActiveGate group

Choose the ActiveGate group to determine which ActiveGates will run the extension. When done, select Next step.

Customize the monitoring

The next step in extension activation is to customize monitoring. See the complete list of feature sets and the metrics collected.

Filters match entity names to include/exclude instances from monitoring. This makes the data more relevant and saves unnecessary license consumption. Filters work with a specific entity type and support the following syntax:

• $eq(<str>) – check if <str> matches what you're filtering
• $prefix(...) – must begin with …
• $suffix(...) - must end with …
• $contains(...) – must contain …
• $and(<expr1>, <expr2>) – can be used to chain two or more of the above expressions with AND operator
• $or(<expr1>, <expr2>) – can be used to chain two or more of the above expressions with OR operator
• $not(<expr>) – can be used to negate an expression

For example, to exclude all Pools from the Common partition, you can add a filter: $not($prefix(/Common/))

The final step is to select Activate, which will communicate the monitoring configuration to the ActiveGate along with the extension that defines how data is being collected.

Data visualization and configuration

The extension is packaged with an overview dashboard that is published as soon as you add it to your environment. Go to Dashboards and look for a preset dashboard called F5 BIGIP LTM Overview.

The dashboard gives an overview into the main components of the platform, as well as shortcuts to the lists of different entity types (in the Navigate to F5 entities section). This is currently the quickest way to navigate to the lists of entities. Otherwise, you can manually add the path into your URL bar: .../ui/entity/list/<entity-type>

Access individual entities from a list or by drilling down from one of the charts in order to get the full details:

Troubleshooting

Configuration status not OK

Whenever a monitoring configuration is created or updated, it can take a few minutes to fully activate and start monitoring. Until then, the configuration status may change to Warning or Error as the configuration gets scheduled to the endpoint, queued for downloading, activated, validated, and starts running. Allow at least 5 minutes for this. If the status is still not OK, select the colored dot next to it; this will open a Log Viewer interface for more details.

Fastcheck failures

Fastcheck is a simple SNMP Get query that aims to retrieve one OID from the device representing its system name. The device has 18 seconds to respond, otherwise the check fails. This is the very first step before any other detail is collected from the device.

Fastcheck failures point to an issue with communicating with the device

• Wrong credentials for connecting to the device
• Network firewalls not allowing communication
• Misconfigured devices not allowing SNMP queries

GetBulk returned an error

GetBulk is the SNMP query operation used to retrieve data from the F5 Device. When this appears in the error message, it means the device is reachable (FastCheck passed) but the data could not be retrieved.

This type of error can have multiple causes:

• The credentials provided (for example, community string) are invalid
• The network is unreliable, causing communication issues
• There is too much data to retrieve; try reducing the feature sets or optimizing the advanced settings

Invalid config errors

Invalid config will point back to the details entered in the monitoring configuration fields. While the Device details are self-explanatory, the variables filters must follow the syntax mentioned the previous section.

High CPU

HIGH_CPU status means the maximum allowed CPU consumption for the datasource module of the Extension Execution Controller (EEC) has been reached on the ActiveGate.

• The amount of data cannot be collected and processed without going above the 5% CPU usage built-in resource limit.
• Try initially enabling fewer feature sets (implying less metrics, so less requests to process) or, alternatively, spread the feature sets over multiple configurations.

Extension logs

Extension logs can be found at ActiveGate directories. Look for the Extensions 2.0 configuration, logs in Purpose of column.

Optimization for large devices

Monitoring configurations are provided with a set of advanced settings which impact how the data is being requested from the device via SNMP. The default values will work in most cases, but you can adjust these if you are experiencing issues, for example you're missing data:

• Timeout and Retries refer to the maximum time to wait for an SNMP query to return and the number of times to retry a query in case of failures.
• Max. repetitions refers to how many times an OID (metric identifier in SNMP) can be repeated as part of a single SNMP GetBulk query response when the same metric is collected for multiple objects/instances. A lower value means more requests between the extension and the device to collect a large dataset. Due to the speed and unreliability of the SNMP protocol, it is more effective to use a smaller value (for example 20). Default = 50.
• Max. OIDs per query refers to the maximum number of OIDs that can be requested for each SNMP GetBulk query. In very large environments, it's recommended to set it to 5. This improves performance by further splitting the workload into more requests.

Metrics

See the metrics collected by the extension broken down into feature sets

• N/A

• instance-memory-basic

• instance-memory-advanced

• instance-sync

• instance-cpu-basic

• disk

• interface

• pool-basic

• pool-advanced

• node-basic

• node-advanced

• virtualserver-basic

• virtualserver-advanced

• profile-serverssl