FAQ for the Logging agent
Frequently asked questions about the Logging agent.
Is there a recommended setting for the Workers configuration for the Logging agent?
A worker, in the context of the Logging agent, represents a CPU thread that is available to the Logging agent for handling logs. You can configure the number of available workers that are available in the output plugin configuration.
The Workers
configuration setting for the output plug-in depends on the log volume being processed. See the agent workers configuration considerations which describes the logs that you can look for to help determine the appropriate setting for your environment.
For example, the Logging agent is deployed as a Daemonset in a Kubernetes or OpenShift cluster. 1 Logging agent pod is deployed in each worker (node) in the cluster. The Helm charts for Openshift and Kubernetes deployments are configured with 4 workers by default. Each Logging agent pod is configured by default to use 4 fluent-bit workers (or threads) to handle the processing of logs in each pod. You can use the guidance in agent workers configuration considerations to configure the number of workers based on your log volumes.
What do the [input] pausing tail
messages in my agent log mean?
The message [input] pausing tail
is an indication that the buffers managed by the Logging agent are full and that the Logging agent is unable to process any more content from the file so it's pausing the input processing. This can
happen for a number of reasons and the frequency and persistence of the warning message will determine your action.
-
If the logging volume increase is temporary and the message only occurs a few times over an hour and is followed almost immediately by a
[input] resume tail
message, then this is likely a temporary situation and you can safely ignore the message. Some logs might be delayed by less than a minute, but generally speaking you will likely not notice a difference when you review your logs in IBM Cloud Logs. -
If the
[input] resume tail
message does not appear within a few seconds then this might be an indication of a problem sending to IBM Cloud Logs. You should check the network connectivity between the Logging agent and IBM Cloud Logs. Not observing the[input] resume tail
message may also be an indication of an IBM Cloud Logs service disruption. -
If the
[input] resume tail
and[input] pausing tail
messages occur more than 30 times within 5 minutes, this is typically an indication that the agent is not configured appropriately to handle the log volume that the agent is processing. This can usually be corrected by increasing theWorkers
configuration in the output plug-in, increasing the CPU limit assigned to the agent process or both actions. See the agent workers configuration considerations for more details. -
Consider reviewing the logs that are being collected and determine whether all of the logs are required. See the Filtering logs topic for ways that you can reduce the volume of logs sent from the Logging agent to IBM Cloud Logs.
How can I send my kube audit logs to IBM Cloud Logs?
If you have configured kube auditing, when you use IBM Cloud Logs you need to install the IBM Cloud Logs agent.
You also need to change the Path
in the tail
INPUT
section of the input-kubernetes.conf
file to include:
/var/log/kubelet/kubelet.log,/var/log/syslog
For more information about the input-kubernetes.conf
file, see Configuring whether logs are included or excluded.