GCP Stackdriver Logs Sink

The Vector gcp_stackdriver_logs sink sends logs to GCP Operations (formerly Stackdriver) logs.

Configuration

[sinks.my_sink_id]
# General
type = "gcp_stackdriver_logs" # required
inputs = ["my-source-or-transform-id"] # required
credentials_path = "/path/to/credentials.json" # optional, no default
healthcheck = true # optional, default
log_id = "vector-logs" # required
project_id = "vector-123456" # required
# Encoding
  • optionaltable

    batch

    Configures the sink batching behavior.

    • commonoptionaluint

      max_bytes

      The maximum size of a batch, in bytes, before it is flushed.

      • Default: 5242880 (bytes)
    • commonoptionaluint

      timeout_secs

      The maximum age of a batch before it is flushed. See Buffers & batches for more info.

      • Default: 1 (seconds)
  • optionalstring

    billing_account_id

    The billing account ID to which to publish logs.

    Exactly one of billing_account_id, folder_id, organization_id, or project_id must be set.

    • View examples
  • optionaltable

    buffer

    Configures the sink specific buffer behavior.

    • commonoptionaluint

      max_events

      The maximum number of events allowed in the buffer. See Buffers & batches for more info.

      • Only relevant when: type = "memory"
      • Default: 500 (events)
    • commonrequired*uint

      max_size

      The maximum size of the buffer on the disk. See Buffers & batches for more info.

      • Only required when: type = "disk"
      • View examples
    • enumcommonoptionalstring

      type

      The buffer's type and storage mechanism.

      • Default: "memory"
      • Enum, must be one of: "memory" "disk"
      • View examples
    • enumoptionalstring

      when_full

      The behavior when the buffer becomes full.

      • Default: "block"
      • Enum, must be one of: "block" "drop_newest"
      • View examples
  • commonoptionalstring

    credentials_path

    The filename for a Google Cloud service account credentials JSON file used to authenticate access to the Stackdriver Logging API. If this is unset, Vector checks the GOOGLE_APPLICATION_CREDENTIALS environment variable for a filename.

    If no filename is named, Vector will attempt to fetch an instance service account for the compute instance the program is running on. If Vector is not running on a GCE instance, you must define a credentials file as above. See GCP Authentication for more info.

    • View examples
  • commonrequiredtable

    encoding

    Configures the encoding specific sink behavior.

    • optional[string]

      except_fields

      Prevent the sink from encoding the specified labels.

      • View examples
    • optional[string]

      only_fields

      Prevent the sink from encoding the specified labels.

      • View examples
    • enumoptionalstring

      timestamp_format

      How to format event timestamps.

      • Default: "rfc3339"
      • Enum, must be one of: "rfc3339" "unix"
      • View examples
  • optionalstring

    folder_id

    The folder ID to which to publish logs. See the Google Cloud Platform folder documentation for more details.

    Exactly one of billing_account_id, folder_id, organization_id, or project_id must be set.

    • View examples
  • commonoptionalbool

    healthcheck

    Enables/disables the sink healthcheck upon Vector boot. See Health checks for more info.

    • Default: true
    • View examples
  • commonrequiredstring

    log_id

    The log ID to which to publish logs. This is a name you create to identify this log stream.

    • View examples
  • optionalstring

    organization_id

    The organization ID to which to publish logs. This would be the identifier assigned to your organization on Google Cloud Platform.

    Exactly one of billing_account_id, folder_id, organization_id, or project_id must be set.

    • View examples
  • commonrequiredstring

    project_id

    The project ID to which to publish logs. See the Google Cloud Platform project management documentation for more details.

    Exactly one of billing_account_id, folder_id, organization_id, or project_id must be set.

    • View examples
  • optionaltable

    request

    Configures the sink request behavior.

    • optionaltable

      adaptive_concurrency

      Configure the adaptive concurrency algorithms. These values have been tuned by optimizing simulated results. In general you should not need to adjust these.

      • optionalfloat
        decrease_ratio

        The fraction of the current value to set the new concurrency limit when decreasing the limit. Valid values are greater than 0 and less than 1. Smaller values cause the algorithm to scale back rapidly when latency increases. Note that the new limit is rounded down after applying this ratio.

        • Default: 0.9
      • optionalfloat
        ewma_alpha

        The adaptive concurrency algorithm uses an exponentially weighted moving average (EWMA) of past RTT measurements as a reference to compare with the current RTT. This value controls how heavily new measurements are weighted compared to older ones. Valid values are greater than 0 and less than 1. Smaller values cause this reference to adjust more slowly, which may be useful if a service has unusually high response variability.

        • Default: 0.7
      • optionalfloat
        rtt_threshold_ratio

        When comparing the past RTT average to the current measurements, we ignore changes that are less than this ratio higher than the past RTT. Valid values are greater than or equal to 0. Larger values cause the algorithm to ignore larger increases in the RTT.

        • Default: 0.05
    • commonoptionaluint

      concurrency

      The maximum number of in-flight requests allowed at any given time, or "auto" to allow Vector to automatically set the limit based on current network and service conditions.

      • Default: 5 (requests)
    • commonoptionaluint

      rate_limit_duration_secs

      The time window, in seconds, used for the rate_limit_num option.

      • Default: 1 (seconds)
    • commonoptionaluint

      rate_limit_num

      The maximum number of requests allowed within the rate_limit_duration_secs time window.

      • Default: 1000
    • optionaluint

      retry_attempts

      The maximum number of retries to make for failed requests. The default, for all intents and purposes, represents an infinite number of retries.

      • Default: 18446744073709552000
    • optionaluint

      retry_initial_backoff_secs

      The amount of time to wait before attempting the first retry for a failed request. Once, the first retry has failed the fibonacci sequence will be used to select future backoffs.

      • Default: 1 (seconds)
    • optionaluint

      retry_max_duration_secs

      The maximum amount of time, in seconds, to wait between retries.

      • Default: 10 (seconds)
    • commonoptionaluint

      timeout_secs

      The maximum time a request can take before being aborted. It is highly recommended that you do not lower this value below the service's internal timeout, as this could create orphaned requests, pile on retries, and result in duplicate data downstream. See Buffers & batches for more info.

      • Default: 60 (seconds)
  • optionaltable

    resource

    Options for describing the logging resource.

    • commonrequiredstring

      type

      The monitored resource type. For example, the type of a Compute Engine VM instance is gce_instance.

      See the Google Cloud Platform monitored resource documentation for more details.

      • View examples
    • optionalstring

      *

      Values for all of the labels listed in the associated monitored resource descriptor.

      For example, Compute Engine VM instances use the labels projectId, instanceId, and zone.

      • View examples
  • optionalstring

    severity_key

    The field of the log event from which to take the outgoing log's severity field. The named field is removed from the log event if present, and must be either an integer between 0 and 800 or a string containing one of the severity level names (case is ignored) or a common prefix such as err. This could be added by an add_fields transform or extracted from a field from the source.

    If no severity key is specified, the severity of outgoing records will be set to 0 (DEFAULT).

    See the GCP Stackdriver Logging LogSeverity description for more details on the value of the severity field. See Severity Level Mapping for more info.

    • View examples
  • optionaltable

    tls

    Configures the TLS options for incoming connections.

    • optionalstring

      ca_file

      Absolute path to an additional CA certificate file, in DER or PEM format (X.509), or an inline CA certificate in PEM format.

      • View examples
    • commonoptionalstring

      crt_file

      Absolute path to a certificate file used to identify this connection, in DER or PEM format (X.509) or PKCS#12, or an inline certificate in PEM format. If this is set and is not a PKCS#12 archive, key_file must also be set.

      • View examples
    • commonoptionalstring

      key_file

      Absolute path to a private key file used to identify this connection, in DER or PEM format (PKCS#8), or an inline private key in PEM format. If this is set, crt_file must also be set.

      • View examples
    • optionalstring

      key_pass

      Pass phrase used to unlock the encrypted key file. This has no effect unless key_file is set.

      • View examples
    • optionalbool

      verify_hostname

      If true (the default), Vector will validate the configured remote host name against the remote host's TLS certificate. Do NOT set this to false unless you understand the risks of not verifying the remote hostname.

      • Default: true
      • View examples

Env Vars

  • commonoptionalstring

    GOOGLE_APPLICATION_CREDENTIALS

    The filename for a Google Cloud service account credentials JSON file used for authentication. See GCP Authentication for more info.

    • Only relevant when: endpoint = null
    • View examples

Telemetry

This component provides the following metrics that can be retrieved through the internal_metrics source. See the metrics section in the monitoring page for more info.

  • counter

    processed_events_total

    The total number of events processed by this component. This metric includes the following tags:

    • component_kind - The Vector component kind.

    • component_name - The Vector component ID.

    • component_type - The Vector component type.

    • file - The file that produced the error

    • instance - The Vector instance identified by host and port.

    • job - The name of the job producing Vector metrics.

  • counter

    processed_bytes_total

    The total number of bytes processed by the component. This metric includes the following tags:

    • component_kind - The Vector component kind.

    • component_name - The Vector component ID.

    • component_type - The Vector component type.

    • instance - The Vector instance identified by host and port.

    • job - The name of the job producing Vector metrics.

How It Works

Buffers & batches

This component buffers & batches data as shown in the diagram above. You'll notice that Vector treats these concepts differently, instead of treating them as global concepts, Vector treats them as sink specific concepts. This isolates sinks, ensuring services disruptions are contained and delivery guarantees are honored.

Batches are flushed when 1 of 2 conditions are met:

  1. The batch age meets or exceeds the configured timeout_secs.
  2. The batch size meets or exceeds the configured <% if component.options.batch.children.respond_to?(:max_size) %>max_size<% else %>max_events<% end %>.

Buffers are controlled via the buffer.* options.

GCP Authentication

GCP offers a variety of authentication methods and Vector is concerned with the server to server methods and will find credentials in the following order:

  1. If the credentials_path option is set.
  2. If the api_key option is set.
  3. If the GOOGLE_APPLICATION_CREDENTIALS envrionment variable is set.
  4. Finally, Vector will check for an instance service account.

If credentials are not found the healtcheck will fail and an error will be logged.

Health checks

Health checks ensure that the downstream service is accessible and ready to accept data. This check is performed upon sink initialization. If the health check fails an error will be logged and Vector will proceed to start.

Require health checks

If you'd like to exit immediately upon a health check failure, you can pass the --require-healthy flag:

vector --config /etc/vector/vector.toml --require-healthy

Disable health checks

If you'd like to disable health checks for this sink you can set the healthcheck option to false.

Partitioning

Vector supports dynamic configuration values through a simple template syntax. If an option supports templating, it will be noted with a badge and you can use event fields to create dynamic values. For example:

vector.toml
[sinks.my-sink]
dynamic_option = "application={{ application_id }}"

In the above example, the application_id for each event will be used to partition outgoing data.

Rate limits & adapative concurrency

Adaptive Request Concurrency (ARC)

Adaptive Requst Concurrency is a feature of Vector that does away with static rate limits and automatically optimizes HTTP concurrency limits based on downstream service responses. The underlying mechanism is a feedback loop inspired by TCP congestion control algorithms. Checkout the announcement blog post,

We highly recommend enabling this feature as it improves performance and reliability of Vector and the systems it communicates with.

To enable, set the request.concurrency option to adaptive:

vector.toml
[sinks.my-sink]
request.concurrency = "adaptive"

Static rate limits

If Adaptive Request Concurrency is not for you, you can manually set static rate limits with the request.rate_limit_duration_secs, request.rate_limit_num, and request.concurrency options:

vector.toml
[sinks.my-sink]
request.rate_limit_duration_secs = 1
request.rate_limit_num = 10
request.concurrency = 10

Retry policy

Vector will retry failed requests (status == 429, >= 500, and != 501). Other responses will not be retried. You can control the number of retry attempts and backoff rate with the request.retry_attempts and request.retry_backoff_secs options.

Severity Level Mapping

If a severity_key is configured, outgoing log records will have their severity header field set from the named field in the Vector event. However, the required values for this field may be inconvenient to produce, typically requiring a custom mapping using an additional transform. To assist with this, this sink remaps certain commonly used words to the required numbers as in the following table. Note that only the prefix is compared, such that a value of emergency matches emerg, and the comparison ignores case.

PrefixValue
emerg800
fatal800
alert700
crit600
err500
warn400
notice300
info200
debug100
trace100

Transport Layer Security (TLS)

Vector uses Openssl for TLS protocols for it's maturity. You can enable and adjust TLS behavior via the tls.* options.