Custom logs collection

Custom k8s logs filtering / storing

By default, groundcover stores logs from all namespaces and workloads in your cluster. However there are multiple ways to modify this behavior.

Filtering Rules

groundcover allows you to add logs filtering rules using LogQL syntax by creating a custom values.yaml file. The available labels to filter are: namespace, workload, pod, level, container. Example of filtering out all logs coming from namespace demo with level info: {namespace="demo",level="info"} In addition, we enable the use of the optional log stream pipeline in order filter the log lines. Example of filtering out all logs coming from container my-container which contain the word fifo or handler: {container="my-container"} |~ "fifo|handler"

More info on LogQL syntax can be found here.

Rules are applied sequentially and independently. Therefore, rules which are meant to specify multiple values of the same label should be written as one rule with multiple options, and not many rules with one option each. For example, a rule to drop logs from all namespaces except prod and dev should be written as: {namespace!="prod", namespace!="dev"}

Usage

values.yaml example

logsDropFilters:
 - '{namespace="demo-ng",workload="loadgenerator"} |~ ".*GET.*"'
 - '{namespace="demo-ng",workload="currencyservice"} !~ "received"'

Using CLI on New or Existing Installation

groundcover deploy --values values.yaml

Using Helm

helm upgrade -i  \
    groundcover \
    groundcover/groundcover \
    -n groundcover \
    -i \
    -f values.yaml

If upgrading an existing installation with different values, consider passing --reuse-values.

Configure Journal Logs

groundcover collects kubelet logs on Kubernetes clusters and docker logs on host machines. You can customize this behavior through additional configuration options.

Usage

Helm Values

journalScraper:
  serviceNames: ["kubelet", "kernel"]  # List of systemd service units to capture logs from
  historyDuration: 10m                 # How far back in time to collect logs when discovering new files
  journalFilter: "system.journal"      # Journal file pattern to match (e.g., "*.journal")
  includeRemoteJournals: true          # Enable collection of journals beyond the current machine-id

Host Overrides

Configure Log File Targets

groundcover can collect logs from specific files on your host machine. You can define paths to monitor and add custom labels to the collected logs.

Usage

Helm Values

logFileTargets:
  - path: "/var/log/syslog.*" # Path pattern to match log files
    excludedPath: "*.gz"      # Pattern to exclude from matched files
    labels:                   # Custom labels to attach to collected logs
      label1: "value1"
    workload: "syslog"        # Optional: Set a custom workload name

Host Overrides

Customize Multi line logs

This enables merging multiple logs lines into a single log block. A new block is defined using a pre-define firstLineRegex , which should match the line prefix. A block is terminated when one of the following conditions is met:

• A new block is matched

• Timeout has occurred (optional config, default is 3 seconds)

• Max number of lines-per-block is reached (optional config, default is 1024 lines)

Configuration holds also workload & namespace fields, which can be set to .* in order to use wildcard logic. An additional optional container field can be added.

Usage

Helm Values

logsMultiLines:
  - namespace: "test-namespace"
    workload: ".*"
    container: "test-container"    # optional
    firstLineRegex: "^\\[\\d{4}-\\d{2}-\\d{2} \\d{1,2}:\\d{2}:\\d{2}\\]"
    maxLines: 100                  # optional, default = 1024
    maxWaitTime: "10s"             # optional, default = 3s

Host Overrides

Example

[2023-08-13 12:00:00] Exception!
Traceback (most recent call last):
  File "/path/to/example.py", line 4, in <module>
    greet('Chad')
  File "/path/to/example.py", line 2, in greet
    print('Hello, ' + someon)
NameError: name 'someon' is not defined
[2023-08-13 12:00:01] Next log line

This will merge all exception logs into a single block line.

Custom parsing with OTTL pipelines

groundcover supports using OTTL pipelines for custom parsing such as Grok patterns, key-value extraction and more.

Instructions for setting up OTTL rules can be found here.

Customize logs decolorization

This feature enable removing ANSI color codes from logs' body.

Usage

decolorizeLogs: true

Example

[2023-10-31 20:38:57.123] \033[0;32HTTP\033[0m: GET /_healthz (1 ms) 204

Will be stripped into:

[2023-10-31 20:38:57.123] HTTP: GET /_healthz (1 ms) 204

Control logs truncation

Use this customization carefully as it might heavily effect the performance of the groundcover sensors.

Body VS Content:

During log parsing groundcover generates two attributes named content and body:

1. body - contains the full log line

2. content - contains the message field of structured logs (from msg/message attribute) or the full log line for unstructured logs

In the platform UI the attribute displayed is the content, while body is available in the DB.

Example:

Formatted log with message: {"time": "Jun 09 2023 15:28:14", "severity": "info", "msg": "Hello World"}

Body: {"time": "Jun 09 2023 15:28:14", "severity": "info", "msg": "Hello World"}
Content: "Hello World"

Unformatted log: [Jun 09 2023 15:28:14], Hello World

Body: "[Jun 09 2023 15:28:14], Hello World"
Content: "[Jun 09 2023 15:28:14], Hello World"

Truncation Config:

The following values contain the default truncation size for body and content respectively:

Up to sensor version 1.11.113 the max content size was 5KB, and increased to 15KB in version 1.11.114

maxLogSize: 102400 # 100KB
maxLogContentSize: 15360 # 15KB