Amazon CloudWatch
Send logs and metrics to Amazon CloudWatch
Last updated
Send logs and metrics to Amazon CloudWatch
Last updated
The Amazon CloudWatch output plugin allows to ingest your records into the CloudWatch Logs service. Support for CloudWatch Metrics is also provided via EMF.
This is the documentation for the core Fluent Bit CloudWatch plugin written in C. It can replace the aws/amazon-cloudwatch-logs-for-fluent-bit Golang Fluent Bit plugin released last year. The Golang plugin was named cloudwatch
; this new high performance CloudWatch plugin is called cloudwatch_logs
to prevent conflicts/confusion. Check the amazon repo for the Golang plugin for details on the deprecation/migration plan for the original plugin.
In order to send records into Amazon Cloudwatch, you can run the plugin from the command line or through the configuration file:
The cloudwatch plugin, can read the parameters from the command line through the -p argument (property), e.g:
In your main configuration file append the following Output section:
Fluent Bit has different input plugins (cpu, mem, disk, netif) to collect host resource usage metrics. cloudwatch_logs
output plugin can be used to send these host metrics to CloudWatch in Embedded Metric Format (EMF). If data comes from any of the above mentioned input plugins, cloudwatch_logs
output plugin will convert them to EMF format and sent to CloudWatch as JSON log. Additionally, if we set json/emf
as the value of log_format
config option, CloudWatch will extract custom metrics from embedded JSON payload.
Note: Right now, only cpu
and mem
metrics can be sent to CloudWatch.
For using the mem
input plugin and sending memory usage metrics to CloudWatch, we can consider the following example config file. Here, we use the aws
filter which adds ec2_instance_id
and az
(availability zone) to the log records. Later, in the output config section, we set ec2_instance_id
as our metric dimension.
The following config will set two dimensions to all of our metrics- ec2_instance_id
and az
.
Amazon distributes a container image with Fluent Bit and these plugins.
github.com/aws/aws-for-fluent-bit
Our images are available in Amazon ECR Public Gallery. You can download images with different tags by following command:
For example, you can pull the image with latest version by:
If you see errors for image pull limits, try log into public ECR with your AWS credentials:
You can check the Amazon ECR Public official doc for more details
You can use our SSM Public Parameters to find the Amazon ECR image URI in your region:
For more see the AWS for Fluent Bit github repo.
Key
Description
region
The AWS region.
log_group_name
The name of the CloudWatch Log Group that you want log records sent to.
log_stream_name
The name of the CloudWatch Log Stream that you want log records sent to.
log_stream_prefix
Prefix for the Log Stream name. The tag is appended to the prefix to construct the full log stream name. Not compatible with the log_stream_name option.
log_key
By default, the whole log record will be sent to CloudWatch. If you specify a key name with this option, then only the value of that key will be sent to CloudWatch. For example, if you are using the Fluentd Docker log driver, you can specify log_key log
and only the log message will be sent to CloudWatch.
log_format
An optional parameter that can be used to tell CloudWatch the format of the data. A value of json/emf enables CloudWatch to extract custom metrics embedded in a JSON payload. See the Embedded Metric Format.
role_arn
ARN of an IAM role to assume (for cross account access).
auto_create_group
Automatically create the log group. Valid values are "true" or "false" (case insensitive). Defaults to false.
endpoint
Specify a custom endpoint for the CloudWatch Logs API.
metric_namespace
An optional string representing the CloudWatch namespace for the metrics. See Metrics Tutorial
section below for a full configuration.
metric_dimensions
A list of lists containing the dimension keys that will be applied to all metrics. The values within a dimension set MUST also be members on the root-node. For more information about dimensions, see Dimension and Dimensions. In the fluent-bit config, metric_dimensions is a comma and semicolon seperated string. If you have only one list of dimensions, put the values as a comma seperated string. If you want to put list of lists, use the list as semicolon seperated strings. For example, if you set the value as 'dimension_1,dimension_2;dimension_3', we will convert it as [[dimension_1, dimension_2],[dimension_3]]
sts_endpoint
Specify a custom STS endpoint for the AWS STS API.