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Version: v2.5

Outputs and ClusterOutputs

For the full details on configuring Outputs and ClusterOutputs, see the Banzai Cloud Logging operator documentation.

Configuration

Changes in v2.5.8

The Outputs and ClusterOutputs can now be configured by filling out forms in the Rancher UI.

# Outputs

The Output resource defines where your Flows can send the log messages. Outputs are the final stage for a logging Flow.

The Output is a namespaced resource, which means only a Flow within the same namespace can access it.

You can use secrets in these definitions, but they must also be in the same namespace.

For the details of Output custom resource, see OutputSpec.

The Rancher UI provides forms for configuring the following Output types:

  • Amazon ElasticSearch
  • Azure Storage
  • Cloudwatch
  • Datadog
  • Elasticsearch
  • File
  • Fluentd
  • GCS
  • Kafka
  • Kinesis Stream
  • LogDNA
  • LogZ
  • Loki
  • New Relic
  • Splunk
  • SumoLogic
  • Syslog

The Rancher UI provides forms for configuring the Output type, target, and access credentials if applicable.

For example configuration for each logging plugin supported by the logging operator, see the logging operator documentation.

ClusterOutputs

ClusterOutput defines an Output without namespace restrictions. It is only effective when deployed in the same namespace as the logging operator.

For the details of the ClusterOutput custom resource, see ClusterOutput.

YAML Examples

Once logging is installed, you can use these examples to help craft your own logging pipeline.

Cluster Output to ElasticSearch

Let's say you wanted to send all logs in your cluster to an elasticsearch cluster. First, we create a cluster Output.

apiVersion: logging.banzaicloud.io/v1beta1
kind: ClusterOutput
metadata:
name: "example-es"
namespace: "cattle-logging-system"
spec:
elasticsearch:
host: elasticsearch.example.com
port: 9200
scheme: http

We have created this ClusterOutput, without elasticsearch configuration, in the same namespace as our operator: cattle-logging-system.. Any time we create a ClusterFlow or ClusterOutput, we have to put it in the cattle-logging-system namespace.

Now that we have configured where we want the logs to go, let's configure all logs to go to that ClusterOutput.

apiVersion: logging.banzaicloud.io/v1beta1
kind: ClusterFlow
metadata:
name: "all-logs"
namespace: "cattle-logging-system"
spec:
globalOutputRefs:
- "example-es"

We should now see our configured index with logs in it.

Output to Splunk

What if we have an application team who only wants logs from a specific namespaces sent to a splunk server? For this case, we can use namespaced Outputs and Flows.

Before we start, let's set up that team's application: coolapp.

apiVersion: v1
kind: Namespace
metadata:
name: devteam
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: coolapp
namespace: devteam
labels:
app: coolapp
spec:
replicas: 2
selector:
matchLabels:
app: coolapp
template:
metadata:
labels:
app: coolapp
spec:
containers:
- name: generator
image: paynejacob/loggenerator:latest

With coolapp running, we will follow a similar path as when we created a ClusterOutput. However, unlike ClusterOutputs, we create our Output in our application's namespace.

apiVersion: logging.banzaicloud.io/v1beta1
kind: Output
metadata:
name: "devteam-splunk"
namespace: "devteam"
spec:
splunkHec:
hec_host: splunk.example.com
hec_port: 8088
protocol: http

Once again, let's feed our Output some logs:

apiVersion: logging.banzaicloud.io/v1beta1
kind: Flow
metadata:
name: "devteam-logs"
namespace: "devteam"
spec:
localOutputRefs:
- "devteam-splunk"

Output to Syslog

Let's say you wanted to send all logs in your cluster to an syslog server. First, we create a ClusterOutput:

apiVersion: logging.banzaicloud.io/v1beta1
kind: ClusterOutput
metadata:
name: "example-syslog"
namespace: "cattle-logging-system"
spec:
syslog:
buffer:
timekey: 30s
timekey_use_utc: true
timekey_wait: 10s
flush_interval: 5s
format:
type: json
app_name_field: test
host: syslog.example.com
insecure: true
port: 514
transport: tcp

Now that we have configured where we want the logs to go, let's configure all logs to go to that Output.

apiVersion: logging.banzaicloud.io/v1beta1
kind: ClusterFlow
metadata:
name: "all-logs"
namespace: cattle-logging-system
spec:
globalOutputRefs:
- "example-syslog"

Unsupported Outputs

For the final example, we create an Output to write logs to a destination that is not supported out of the box:

Note on syslog As of Rancher v2.5.4, syslog is a supported Output. However, this example still provides an overview on using unsupported plugins.

apiVersion: v1
kind: Secret
metadata:
name: syslog-config
namespace: cattle-logging-system
type: Opaque
stringData:
fluent-bit.conf: |
[INPUT]
Name forward
Port 24224

[OUTPUT]
Name syslog
InstanceName syslog-output
Match *
Addr syslog.example.com
Port 514
Cluster ranchers

---
apiVersion: apps/v1
kind: Deployment
metadata:
name: fluentbit-syslog-forwarder
namespace: cattle-logging-system
labels:
output: syslog
spec:
selector:
matchLabels:
output: syslog
template:
metadata:
labels:
output: syslog
spec:
containers:
- name: fluentbit
image: paynejacob/fluent-bit-out-syslog:latest
ports:
- containerPort: 24224
volumeMounts:
- mountPath: "/fluent-bit/etc/"
name: configuration
volumes:
- name: configuration
secret:
secretName: syslog-config
---
apiVersion: v1
kind: Service
metadata:
name: syslog-forwarder
namespace: cattle-logging-system
spec:
selector:
output: syslog
ports:
- protocol: TCP
port: 24224
targetPort: 24224
---
apiVersion: logging.banzaicloud.io/v1beta1
kind: ClusterFlow
metadata:
name: all-logs
namespace: cattle-logging-system
spec:
globalOutputRefs:
- syslog
---
apiVersion: logging.banzaicloud.io/v1beta1
kind: ClusterOutput
metadata:
name: syslog
namespace: cattle-logging-system
spec:
forward:
servers:
- host: "syslog-forwarder.cattle-logging-system"
require_ack_response: false
ignore_network_errors_at_startup: false

Let's break down what is happening here. First, we create a deployment of a container that has the additional syslog plugin and accepts logs forwarded from another fluentd. Next we create an Output configured as a forwarder to our deployment. The deployment fluentd will then forward all logs to the configured syslog destination.