VictoriaMetrics/docs/VictoriaLogs/data-ingestion/README.md

VictoriaLogs can accept logs from the following log collectors:

• Syslog, Rsyslog and Syslog-ng - see these docs.
• Filebeat - see these docs.
• Fluentbit - see these docs.
• Fluentd - see these docs.
• Logstash - see these docs.
• Vector - see these docs.
• Promtail (aka Grafana Loki, Grafana Agent or Grafana Alloy) - see these docs.
• Telegraf - see these docs.
• OpenTelemetry Collector - see these docs.
• Journald - see these docs.
• DataDog - see these docs.

The ingested logs can be queried according to these docs.

See also:

• Log collectors and data ingestion formats.
• Data ingestion troubleshooting.

HTTP APIs

VictoriaLogs supports the following data ingestion HTTP APIs:

• Elasticsearch bulk API. See these docs.
• JSON stream API aka ndjson. See these docs.
• Loki JSON API. See these docs.
• OpenTelemetry API. See these docs.
• Journald export format.

VictoriaLogs accepts optional HTTP parameters at data ingestion HTTP APIs.

Elasticsearch bulk API

VictoriaLogs accepts logs in Elasticsearch bulk API / OpenSearch Bulk API format at http://localhost:9428/insert/elasticsearch/_bulk endpoint.

The following command pushes a single log line to VictoriaLogs:

echo '{"create":{}}
{"_msg":"cannot open file","_time":"0","host.name":"host123"}
' | curl -X POST -H 'Content-Type: application/json' --data-binary @- http://localhost:9428/insert/elasticsearch/_bulk

It is possible to push thousands of log lines in a single request to this API.

If the timestamp field is set to "0", then the current timestamp at VictoriaLogs side is used per each ingested log line. Otherwise the timestamp field must be in one of the following formats:

• ISO8601 or RFC3339. For example, 2023-06-20T15:32:10Z or 2023-06-20 15:32:10.123456789+02:00. If timezone information is missing (for example, 2023-06-20 15:32:10), then the time is parsed in the local timezone of the host where VictoriaLogs runs.

• Unix timestamp in seconds or in milliseconds. For example, 1686026893 (seconds) or 1686026893735 (milliseconds).

See these docs for details on fields, which must be present in the ingested log messages.

The API accepts various http parameters, which can change the data ingestion behavior - these docs for details.

The following command verifies that the data has been successfully ingested to VictoriaLogs by querying it:

curl http://localhost:9428/select/logsql/query -d 'query=host.name:host123'

The command should return the following response:

{"_msg":"cannot open file","_stream":"{}","_time":"2023-06-21T04:24:24Z","host.name":"host123"}

The response by default contains all the log fields. See how to query specific fields.

The duration of requests to /insert/elasticsearch/_bulk can be monitored with vl_http_request_duration_seconds{path="/insert/elasticsearch/_bulk"} metric.

See also:

• How to debug data ingestion.
• HTTP parameters, which can be passed to the API.
• How to query VictoriaLogs.

JSON stream API

VictoriaLogs accepts JSON line stream aka ndjson at http://localhost:9428/insert/jsonline endpoint.

The following command pushes multiple log lines to VictoriaLogs:

echo '{ "log": { "level": "info", "message": "hello world" }, "date": "0", "stream": "stream1" }
{ "log": { "level": "error", "message": "oh no!" }, "date": "0", "stream": "stream1" }
{ "log": { "level": "info", "message": "hello world" }, "date": "0", "stream": "stream2" }
' | curl -X POST -H 'Content-Type: application/stream+json' --data-binary @- \
 'http://localhost:9428/insert/jsonline?_stream_fields=stream&_time_field=date&_msg_field=log.message'

It is possible to push unlimited number of log lines in a single request to this API.

If the timestamp field is set to "0", then the current timestamp at VictoriaLogs side is used per each ingested log line. Otherwise the timestamp field must be in one of the following formats:

• ISO8601 or RFC3339. For example, 2023-06-20T15:32:10Z or 2023-06-20 15:32:10.123456789+02:00. If timezone information is missing (for example, 2023-06-20 15:32:10), then the time is parsed in the local timezone of the host where VictoriaLogs runs.

• Unix timestamp in seconds or in milliseconds. For example, 1686026893 (seconds) or 1686026893735 (milliseconds).

See these docs for details on fields, which must be present in the ingested log messages.

The API accepts various http parameters, which can change the data ingestion behavior - these docs for details.

The following command verifies that the data has been successfully ingested into VictoriaLogs by querying it:

curl http://localhost:9428/select/logsql/query -d 'query=log.level:*'

The command should return the following response:

{"_msg":"hello world","_stream":"{stream=\"stream2\"}","_time":"2023-06-20T13:35:11.56789Z","log.level":"info"}
{"_msg":"hello world","_stream":"{stream=\"stream1\"}","_time":"2023-06-20T15:31:23Z","log.level":"info"}
{"_msg":"oh no!","_stream":"{stream=\"stream1\"}","_time":"2023-06-20T15:32:10.567Z","log.level":"error"}

The response by default contains all the log fields. See how to query specific fields.

The duration of requests to /insert/jsonline can be monitored with vl_http_request_duration_seconds{path="/insert/jsonline"} metric.

See also:

• How to debug data ingestion.
• HTTP parameters, which can be passed to the API.
• How to query VictoriaLogs.

Loki JSON API

VictoriaLogs accepts logs in Loki JSON API format at http://localhost:9428/insert/loki/api/v1/push endpoint.

The following command pushes a single log line to Loki JSON API at VictoriaLogs:

curl -H "Content-Type: application/json" -XPOST "http://localhost:9428/insert/loki/api/v1/push?_stream_fields=instance,job" --data-raw \
  '{"streams": [{ "stream": { "instance": "host123", "job": "app42" }, "values": [ [ "0", "foo fizzbuzz bar" ] ] }]}'

It is possible to push thousands of log streams and log lines in a single request to this API.

The API accepts various http parameters, which can change the data ingestion behavior - these docs for details. There is no need in specifying _msg_field and _time_field query args, since VictoriaLogs automatically extracts log message and timestamp from the ingested Loki data.

The following command verifies that the data has been successfully ingested into VictoriaLogs by querying it:

curl http://localhost:9428/select/logsql/query -d 'query=fizzbuzz'

The command should return the following response:

{"_msg":"foo fizzbuzz bar","_stream":"{instance=\"host123\",job=\"app42\"}","_time":"2023-07-20T23:01:19.288676497Z"}

The response by default contains all the log fields. See how to query specific fields.

The duration of requests to /insert/loki/api/v1/push can be monitored with vl_http_request_duration_seconds{path="/insert/loki/api/v1/push"} metric.

See also:

• How to debug data ingestion.
• HTTP parameters, which can be passed to the API.
• How to query VictoriaLogs.

HTTP parameters

VictoriaLogs accepts the following configuration parameters via HTTP headers or via HTTP query string args at data ingestion HTTP APIs. HTTP query string parameters have priority over HTTP Headers.

HTTP Query string parameters

All the HTTP-based data ingestion protocols support the following HTTP query string args:

• _msg_field - the name of the log field containing log message. This is usually the message field for Filebeat and Logstash.

  The _msg_field arg may contain comma-separated list of field names. In this case the first non-empty field from the list is treated as log message.

  If the _msg_field arg isn't set, then VictoriaLogs reads the log message from the _msg field. If the _msg field is empty, then it is set to -defaultMsgValue command-line flag value.

• _time_field - the name of the log field containing log timestamp. This is usually the @timestamp field for Filebeat and Logstash.

  If the _time_field arg isn't set, then VictoriaLogs reads the timestamp from the _time field. If this field doesn't exist, then the current timestamp is used.

• _stream_fields - comma-separated list of log field names, which uniquely identify every log stream.

  If the _stream_fields arg isn't set, then all the ingested logs are written to default log stream - {}.

• ignore_fields - an optional comma-separated list of log field names, which must be ignored during data ingestion.

• extra_fields - an optional comma-separated list log fields, which must be added to all the ingested logs. The format of every extra_fields entry is field_name=field_value. If the log entry contains fields from the extra_fields, then they are overwritten by the values specified in extra_fields.

• debug - if this arg is set to 1, then the ingested logs aren't stored in VictoriaLogs. Instead, the ingested data is logged by VictoriaLogs, so it can be investigated later.

See also HTTP headers.

HTTP headers

All the HTTP-based data ingestion protocols support the following HTTP Headers additionally to HTTP query args:

• AccountID - accountID of the tenant to ingest data to. See multitenancy docs for details.

• ProjectID- projectID of the tenant to ingest data to. See multitenancy docs for details.

• VL-Msg-Field - the name of the log field containing log message. This is usually the message field for Filebeat and Logstash.

  The VL-Msg-Field header may contain comma-separated list of field names. In this case the first non-empty field from the list is treated as log message.

  If the VL-Msg-Field header isn't set, then VictoriaLogs reads log message from the _msg field. If the _msg field is empty, then it is set to -defaultMsgValue command-line flag value.

• VL-Time-Field - the name of the log field containing log timestamp. This is usually the @timestamp field for Filebeat and Logstash.

  If the VL-Time-Field header isn't set, then VictoriaLogs reads the timestamp from the _time field. If this field doesn't exist, then the current timestamp is used.

• VL-Stream-Fields - comma-separated list of log field names, which uniquely identify every log stream.

  If the VL-Stream-Fields header isn't set, then all the ingested logs are written to default log stream - {}.

• VL-Ignore-Fields - an optional comma-separated list of log field names, which must be ignored during data ingestion.

• VL-Extra-Fields - an optional comma-separated list of log fields, which must be added to all the ingested logs. The format of every extra_fields entry is field_name=field_value. If the log entry contains fields from the extra_fields, then they are overwritten by the values specified in extra_fields.

• VL-Debug - if this parameter is set to 1, then the ingested logs aren't stored in VictoriaLogs. Instead, the ingested data is logged by VictoriaLogs, so it can be investigated later.

See also HTTP Query string parameters.

Troubleshooting

The following command can be used for verifying whether the data is successfully ingested into VictoriaLogs:

curl http://localhost:9428/select/logsql/query -d 'query=*' | head

This command selects all the data ingested into VictoriaLogs via HTTP query API using any value filter, while head cancels query execution after reading the first 10 log lines. See these docs for more details on how head integrates with VictoriaLogs.

The response by default contains all the log fields. See how to query specific fields.

VictoriaLogs provides the following command-line flags, which can help debugging data ingestion issues:

• -logNewStreams - if this flag is passed to VictoriaLogs, then it logs all the newly registered log streams. This may help debugging high cardinality issues.
• -logIngestedRows - if this flag is passed to VictoriaLogs, then it logs all the ingested log entries. See also debug parameter.

VictoriaLogs exposes various metrics, which may help debugging data ingestion issues:

• vl_rows_ingested_total - the number of ingested log entries since the last VictoriaLogs restart. If this number increases over time, then logs are successfully ingested into VictoriaLogs. The ingested logs can be inspected in the following ways:
  • By passing debug=1 parameter to every request to data ingestion APIs. The ingested rows aren't stored in VictoriaLogs in this case. Instead, they are logged, so they can be investigated later. The vl_rows_dropped_total metric is incremented for each logged row.
  • By passing -logIngestedRows command-line flag to VictoriaLogs. In this case it logs all the ingested data, so it can be investigated later.
• vl_streams_created_total - the number of created log streams since the last VictoriaLogs restart. If this metric grows rapidly during extended periods of time, then this may lead to high cardinality issues. The newly created log streams can be inspected in logs by passing -logNewStreams command-line flag to VictoriaLogs.

Log collectors and data ingestion formats

Here is the list of log collectors and their ingestion formats supported by VictoriaLogs:

How to setup the collector	Format: Elasticsearch	Format: JSON Stream	Format: Loki	Format: syslog	Format: OpenTelemetry	Format: Journald	Format: DataDog
Rsyslog	Yes	No	No	Yes	No	No	No
Syslog-ng	Yes, v1, v2	No	No	Yes	No	No	No
Filebeat	Yes	No	No	No	No	No	No
Fluentbit	No	Yes	Yes	Yes	Yes	No	Yes
Logstash	Yes	No	No	Yes	Yes	No	Yes
Vector	Yes	Yes	Yes	No	No	No	Yes
Promtail	No	No	Yes	No	No	No	No
OpenTelemetry Collector	Yes	No	Yes	Yes	Yes	No	Yes
Telegraf	Yes	Yes	Yes	Yes	Yes	No	No
Fluentd	Yes	Yes	Yes	Yes	No	No	No
Journald	No	No	No	No	No	Yes	No
DataDog Agent	No	No	No	No	No	No	Yes