I am trying to understand how the blacklist mechanism of the jmx exporter works.
I took an example from here https://github.com/confluentinc/jmx-monitoring-stacks/blob/7.2-post/shared-assets/jmx-exporter/confluent_ksql.yml
At the top of it we have the following blacklist
blacklistObjectNames:
- "io.confluent.ksql.metrics:name=*"
- kafka.streams:type=kafka-metrics-count
# This will ignore the admin client metrics from KSQL server and will blacklist certain metrics
# that do not make sense for ingestion.
- "kafka.admin.client:*"
- "kafka.consumer:type=*,id=*"
- "kafka.consumer:type=*,client-id=*"
- "kafka.consumer:type=*,client-id=*,node-id=*"
- "kafka.producer:type=*,id=*"
- "kafka.producer:type=*,client-id=*"
- "kafka.producer:type=*,client-id=*,node-id=*"
- "kafka.streams:type=stream-processor-node-metrics,thread-id=*,task-id=*,processor-node-id=*"
- "kafka.*:type=kafka-metrics-count,*"
- "io.confluent.ksql.metrics:type=_confluent-ksql-rest-app-command-runner,*"
Yet in the rule pattern we have things like
# "kafka.consumer:type=app-info,client-id=*"
# "kafka.producer:type=app-info,client-id=*"
- pattern: "kafka.(.+)<type=app-info, client-id=(.+)><>(.+): (.+)"
value: 1
name: kafka_$1_app_info
labels:
client_type: $1
client_id: $2
$3: $4
type: UNTYPED
Isn't that rule supposed to not work given
- "kafka.producer:type=*,client-id=*"
Related
am using filebeat to forward incoming logs from haproxy to Kafka topic but after forwarding filebeat is adding so much metadata to the kafka message which consumes more memory which I want to avoid.
Example of message sinked to kafka from filebeat where it is adding metadata, host and lot of other things:
{
"#timestamp": "2017-03-27T08:14:09.508Z",
"beat": {
"hostname": "stage-kube03",
"name": "stage-kube03",
"version": "5.2.1"
},
"input_type": "log",
"message": {
"message": {
"activityType": null
},
"offset": 3783008,
"source": "/var/log/audit.log",
"type": "log"
}
How do I control/reduce the additional metadata filebeat adds to kafka message along with the log line payload? below is my filebeat.yml file
###################### Filebeat Configuration Example #########################
# This file is an example configuration file highlighting only the most common
# options. The filebeat.reference.yml file from the same directory contains all the
# supported options with more comments. You can use it as a reference.
#
# You can find the full configuration reference here:
# https://www.elastic.co/guide/en/beats/filebeat/index.html
# For more available modules and options, please see the filebeat.reference.yml sample
# configuration file.
#=========================== Filebeat inputs =============================
filebeat.inputs:
# Each - is an input. Most options can be set at the input level, so
# you can use different inputs for various configurations.
# Below are the input specific configurations.
- type: log
# Change to true to enable this input configuration.
enabled: true
# Paths that should be crawled and fetched. Glob based paths.
paths:
- /var/log/haproxy.log
#exclude_files: [".gz$"]
#fields:
# codec: plain
# token: USER_TOKEN
# type: haproxy_log
#fields_under_root: true
#- c:\programdata\elasticsearch\logs\*
processors:
- drop_event:
# fields: ["prospector","event","dataset"]
# Exclude lines. A list of regular expressions to match. It drops the lines that are
# matching any regular expression from the list.
#exclude_lines: ['^DBG']
exclude_lines: ['^source']
# Include lines. A list of regular expressions to match. It exports the lines that are
# matching any regular expression from the list.
#include_lines: ['^ERR', '^WARN']
# Exclude files. A list of regular expressions to match. Filebeat drops the files that
# are matching any regular expression from the list. By default, no files are dropped.
#exclude_files: ['.gz$']
# Optional additional fields. These fields can be freely picked
# to add additional information to the crawled log files for filtering
#fields:
# level: debug
# review: 1
### Multiline options
# Multiline can be used for log messages spanning multiple lines. This is common
# for Java Stack Traces or C-Line Continuation
# The regexp Pattern that has to be matched. The example pattern matches all lines starting with [
#multiline.pattern: ^\[
# Defines if the pattern set under pattern should be negated or not. Default is false.
#multiline.negate: false
# Match can be set to "after" or "before". It is used to define if lines should be append to a pattern
# that was (not) matched before or after or as long as a pattern is not matched based on negate.
# Note: After is the equivalent to previous and before is the equivalent to to next in Logstash
#multiline.match: after
#============================= Filebeat modules ===============================
filebeat.config.modules:
# Glob pattern for configuration loading
path: ${path.config}/modules.d/*.yml
# Set to true to enable config reloading
reload.enabled: false
# Period on which files under path should be checked for changes
#reload.period: 10s
#==================== Elasticsearch template setting ==========================
setup.template.settings:
index.number_of_shards: 3
#index.codec: best_compression
#_source.enabled: false
#================================ General =====================================
# The name of the shipper that publishes the network data. It can be used to group
# all the transactions sent by a single shipper in the web interface.
#name:
# The tags of the shipper are included in their own field with each
# transaction published.
#tags: ["service-X", "web-tier"]
# Optional fields that you can specify to add additional information to the
# output.
#fields:
# env: staging
#============================== Dashboards =====================================
# These settings control loading the sample dashboards to the Kibana index. Loading
# the dashboards is disabled by default and can be enabled either by setting the
# options here, or by using the `-setup` CLI flag or the `setup` command.
#setup.dashboards.enabled: false
# The URL from where to download the dashboards archive. By default this URL
# has a value which is computed based on the Beat name and version. For released
# versions, this URL points to the dashboard archive on the artifacts.elastic.co
# website.
#setup.dashboards.url:
#============================== Kibana =====================================
# Starting with Beats version 6.0.0, the dashboards are loaded via the Kibana API.
# This requires a Kibana endpoint configuration.
setup.kibana:
# Kibana Host
# Scheme and port can be left out and will be set to the default (http and 5601)
# In case you specify and additional path, the scheme is required: http://localhost:5601/path
# IPv6 addresses should always be defined as: https://[2001:db8::1]:5601
#host: "localhost:5601"
# Kibana Space ID
# ID of the Kibana Space into which the dashboards should be loaded. By default,
# the Default Space will be used.
#space.id:
#============================= Elastic Cloud ==================================
# These settings simplify using filebeat with the Elastic Cloud (https://cloud.elastic.co/).
# The cloud.id setting overwrites the `output.elasticsearch.hosts` and
# `setup.kibana.host` options.
# You can find the `cloud.id` in the Elastic Cloud web UI.
#cloud.id:
# The cloud.auth setting overwrites the `output.elasticsearch.username` and
# `output.elasticsearch.password` settings. The format is `<user>:<pass>`.
#cloud.auth:
#================================ Outputs =====================================
# Configure what output to use when sending the data collected by the beat.
#-------------------------- Elasticsearch output ------------------------------
#output.elasticsearch:
# Array of hosts to connect to.
# hosts: ["localhost:9200"]
# Enabled ilm (beta) to use index lifecycle management instead daily indices.
#ilm.enabled: false
# Optional protocol and basic auth credentials.
#protocol: "https"
#username: "elastic"
#password: "changeme"
#----------------------------- Logstash output --------------------------------
#output.logstash:
# The Logstash hosts
#hosts: ["localhost:5044"]
# Optional SSL. By default is off.
# List of root certificates for HTTPS server verifications
#ssl.certificate_authorities: ["/etc/pki/root/ca.pem"]
# Certificate for SSL client authentication
#ssl.certificate: "/etc/pki/client/cert.pem"
# Client Certificate Key
#ssl.key: "/etc/pki/client/cert.key"
#================================ Processors =====================================
# Configure processors to enhance or manipulate events generated by the beat.
processors:
- add_host_metadata: ~
- add_cloud_metadata: ~
#================================ Logging =====================================
# Sets log level. The default log level is info.
# Available log levels are: error, warning, info, debug
#logging.level: debug
# At debug level, you can selectively enable logging only for some components.
# To enable all selectors use ["*"]. Examples of other selectors are "beat",
# "publish", "service".
#logging.selectors: ["*"]
#============================== Xpack Monitoring ===============================
# filebeat can export internal metrics to a central Elasticsearch monitoring
# cluster. This requires xpack monitoring to be enabled in Elasticsearch. The
# reporting is disabled by default.
# Set to true to enable the monitoring reporter.
#xpack.monitoring.enabled: false
# Uncomment to send the metrics to Elasticsearch. Most settings from the
# Elasticsearch output are accepted here as well. Any setting that is not set is
# automatically inherited from the Elasticsearch output configuration, so if you
# have the Elasticsearch output configured, you can simply uncomment the
# following line.
#xpack.monitoring.elasticsearch:
output.kafka:
hosts: ["10.12.0.90:9092"]
topic: "data-meter-topic"
codec.json:
pretty: true
You need to remove the additional add_host_metadata and add_cloud_metadata metadata you're adding explicitly and remove the remainder of the fields with the drop_field processor:
I've tested your configuration and changed the following:
filebeat.inputs:
- type: log
enabled: true
paths:
- /var/log/*.log
output.console:
pretty: true
processors:
- drop_fields:
fields: ["agent", "log", "input", "host", "ecs" ]
#- add_host_metadata: ~
#- add_cloud_metadata: ~
The result:
{
"#timestamp": "2020-11-27T15:55:17.098Z",
"#metadata": {
"beat": "filebeat",
"type": "_doc",
"version": "7.10.0"
},
"message": "2020-11-27 00:29:58 status installed libc-bin:amd64 2.28-10"
}
According to the documentation, you can't remove some of the metadata, namely the #timestamp and type (which should include the #metadata field).
The drop_fields processor specifies which fields to drop if a certain
condition is fulfilled. The condition is optional. If it’s missing,
the specified fields are always dropped. The #timestamp and type
fields cannot be dropped, even if they show up in the drop_fields
list.
EDIT:
Since you appear to be running filebeat 5.2.1, I've tried the following configuration with even better success than filebeat 7.x:
filebeat.prospectors:
- input_type: log
paths:
- /var/log/*.log
output.console:
pretty: true
processors:
- drop_fields:
fields: ["log_type", "input_type", "offset", "beat", "source"]
Result:
{
"#timestamp": "2020-11-30T09:51:40.404Z",
"message": "2020-11-27 00:29:58 status half-configured vim:amd64 2:8.1.0875-5",
"type": "log"
}
EDIT2:
Conversely, because you've posted a filebeat 6.8.0 version output, I've also tested with this very same version:
filebeat.inputs:
- type: log
enabled: true
paths:
- /var/log/*.log
output.console:
pretty: true
processors:
- drop_fields:
fields: ["beat", "source", "prospector", "offset", "host", "log", "input", "event", "fileset" ]
#- add_host_metadata: ~
#- add_cloud_metadata: ~
Output:
{
"#timestamp": "2020-11-30T10:08:26.176Z",
"#metadata": {
"beat": "filebeat",
"type": "doc",
"version": "6.8.0"
},
"message": "2020-11-27 00:29:58 status unpacked vim:amd64 2:8.1.0875-5"
}
I have added output.mongodb in filebeat.yml file but it is showing error "Exiting: error initializing publisher: output type mongodb undefined"
Does anyone here has any different fail safe approach towards this requirement where I want to redirect filebeat output directly to mongo database?
Filbeat.yml file
###################### Filebeat Configuration Example #########################
# This file is an example configuration file highlighting only the most common
# options. The filebeat.reference.yml file from the same directory contains all the
# supported options with more comments. You can use it as a reference.
#
# You can find the full configuration reference here:
# https://www.elastic.co/guide/en/beats/filebeat/index.html
# For more available modules and options, please see the filebeat.reference.yml sample
# configuration file.
#=========================== Filebeat inputs =============================
filebeat.inputs:
# Each - is an input. Most options can be set at the input level, so
# you can use different inputs for various configurations.
# Below are the input specific configurations.
- type: log
# Change to true to enable this input configuration.
enabled: true
# Paths that should be crawled and fetched. Glob based paths.
paths:
- /var/log/test.log
#- c:\programdata\elasticsearch\logs\*
# Exclude lines. A list of regular expressions to match. It drops the lines that are
# matching any regular expression from the list.
#exclude_lines: ['^DBG']
# Include lines. A list of regular expressions to match. It exports the lines that are
# matching any regular expression from the list.
#include_lines: ['^ERR', '^WARN']
# Exclude files. A list of regular expressions to match. Filebeat drops the files that
# are matching any regular expression from the list. By default, no files are dropped.
#exclude_files: ['.gz$']
# Optional additional fields. These fields can be freely picked
# to add additional information to the crawled log files for filtering
#fields:
# level: debug
# review: 1
### Multiline options
# Multiline can be used for log messages spanning multiple lines. This is common
# for Java Stack Traces or C-Line Continuation
# The regexp Pattern that has to be matched. The example pattern matches all lines starting with [
#multiline.pattern: ^\[
# Defines if the pattern set under pattern should be negated or not. Default is false.
#multiline.negate: false
# Match can be set to "after" or "before". It is used to define if lines should be append to a pattern
# that was (not) matched before or after or as long as a pattern is not matched based on negate.
# Note: After is the equivalent to previous and before is the equivalent to to next in Logstash
#multiline.match: after
#============================= Filebeat modules ===============================
filebeat.config.modules:
# Glob pattern for configuration loading
path: ${path.config}/modules.d/*.yml
# Set to true to enable config reloading
reload.enabled: false
# Period on which files under path should be checked for changes
reload.period: 5s
#==================== Elasticsearch template setting ==========================
setup.template.settings:
index.number_of_shards: 2
#index.codec: best_compression
#_source.enabled: false
#================================ General =====================================
# The name of the shipper that publishes the network data. It can be used to group
# all the transactions sent by a single shipper in the web interface.
#name:
# The tags of the shipper are included in their own field with each
# transaction published.
#tags: ["service-X", "web-tier"]
# Optional fields that you can specify to add additional information to the
# output.
#fields:
# env: staging
#============================== Dashboards =====================================
# These settings control loading the sample dashboards to the Kibana index. Loading
# the dashboards is disabled by default and can be enabled either by setting the
# options here or by using the `setup` command.
#setup.dashboards.enabled: false
# The URL from where to download the dashboards archive. By default this URL
# has a value which is computed based on the Beat name and version. For released
# versions, this URL points to the dashboard archive on the artifacts.elastic.co
# website.
#setup.dashboards.url:
#============================== Kibana =====================================
# Starting with Beats version 6.0.0, the dashboards are loaded via the Kibana API.
# This requires a Kibana endpoint configuration.
setup.kibana:
# Kibana Host
# Scheme and port can be left out and will be set to the default (http and 5601)
# In case you specify and additional path, the scheme is required: http://localhost:5601/path
# IPv6 addresses should always be defined as: https://[2001:db8::1]:5601
host: "10.27.3.235:5601"
# Kibana Space ID
# ID of the Kibana Space into which the dashboards should be loaded. By default,
# the Default Space will be used.
#space.id:
#============================= Elastic Cloud ==================================
# These settings simplify using Filebeat with the Elastic Cloud (https://cloud.elastic.co/).
# The cloud.id setting overwrites the `output.elasticsearch.hosts` and
# `setup.kibana.host` options.
# You can find the `cloud.id` in the Elastic Cloud web UI.
#cloud.id:
# The cloud.auth setting overwrites the `output.elasticsearch.username` and
# `output.elasticsearch.password` settings. The format is `<user>:<pass>`.
#cloud.auth:
#================================ Outputs =====================================
# Configure what output to use when sending the data collected by the beat.
#-------------------------- Elasticsearch output ------------------------------
# output.elasticsearch:
# # Array of hosts to connect to.
# # hosts: ["10.27.3.235:9200"]
# hosts: ["http://10.27.3.235:9200"]
# index: "filebeatSYS-%{[agent.version]}-%{+yyyy.MM.dd}"
# setup.template:
# name: 'api-access'
# pattern: 'api-access-*'
# enabled: false
#
# # Optional protocol and basic auth credentials.
# #protocol: "https"
# #username: "elastic"
# #password: "changeme"
# #index: "filebeat-%{+yyyy.MM.dd}"
#-------------------------- MongoDB output ------------------------------
output.mongodb:
enabled: true
# URL format, according to mgo.v2 doc : [mongodb://][user:pass#]host1[:port1][,host2[:port2],...][/database][?options]
# More info : https://godoc.org/gopkg.in/mgo.v2#Dial
hosts: ["mongodb://<my-db-url-inserted-here>:27017"]
# The mongodb database to push to
db: "<my-db-here>"
# The database collection to push to
# Could be configured like key/keys of the Redis output : https://www.elastic.co/guide/en/beats/filebeat/current/redis-output.html#_key_2
collection: "filebeat"
# https://www.elastic.co/guide/en/beats/filebeat/current/redis-output.html#_loadbalance
loadbalance: true
# https://www.elastic.co/guide/en/beats/filebeat/current/redis-output.html#_timeout_4
timeout: 5s
# https://www.elastic.co/guide/en/beats/filebeat/current/redis-output.html#_max_retries_4
max_retries: 5
# https://www.elastic.co/guide/en/beats/filebeat/current/redis-output.html#_bulk_max_size_4
bulk_max_size: 2048
#----------------------------- Logstash output --------------------------------
#output.logstash:
# The Logstash hosts
#hosts: ["localhost:5044"]
# Optional SSL. By default is off.
# List of root certificates for HTTPS server verifications
#ssl.certificate_authorities: ["/etc/pki/root/ca.pem"]
# Certificate for SSL client authentication
#ssl.certificate: "/etc/pki/client/cert.pem"
# Client Certificate Key
#ssl.key: "/etc/pki/client/cert.key"
#================================ Processors =====================================
# Configure processors to enhance or manipulate events generated by the beat.
processors:
- add_host_metadata: ~
- add_cloud_metadata: ~
- add_docker_metadata: ~
- add_kubernetes_metadata: ~
#================================ Logging =====================================
# Sets log level. The default log level is info.
# Available log levels are: error, warning, info, debug
#logging.level: debug
# At debug level, you can selectively enable logging only for some components.
# To enable all selectors use ["*"]. Examples of other selectors are "beat",
# "publish", "service".
#logging.selectors: ["*"]
#============================== X-Pack Monitoring ===============================
# filebeat can export internal metrics to a central Elasticsearch monitoring
# cluster. This requires xpack monitoring to be enabled in Elasticsearch. The
# reporting is disabled by default.
# Set to true to enable the monitoring reporter.
#monitoring.enabled: false
# Sets the UUID of the Elasticsearch cluster under which monitoring data for this
# Filebeat instance will appear in the Stack Monitoring UI. If output.elasticsearch
# is enabled, the UUID is derived from the Elasticsearch cluster referenced by output.elasticsearch.
#monitoring.cluster_uuid:
# Uncomment to send the metrics to Elasticsearch. Most settings from the
# Elasticsearch output are accepted here as well.
# Note that the settings should point to your Elasticsearch *monitoring* cluster.
# Any setting that is not set is automatically inherited from the Elasticsearch
# output configuration, so if you have the Elasticsearch output configured such
# that it is pointing to your Elasticsearch monitoring cluster, you can simply
# uncomment the following line.
#monitoring.elasticsearch:
#================================= Migration ==================================
# This allows to enable 6.7 migration aliases
#migration.6_to_7.enabled: true
You get the error
Exiting: error initializing publisher: output type mongodb undefined
because Filebeat does not support this kind of output. Take a look at the Output Configuration doc of Filebeat. There is no output for MongoDB mentioned. Filebeat supports only the following outputs:
Elasticsearch
Logstash
Kafka
Redis
File
Console
Elastic Cloud
By defining
output.mongodb:
Filebeat crashes because 'mongodb' is an unknown/undefined configuration-field in the output-element.
Does anyone here has any different fail safe approach towards this requirement where I want to redirect filebeat output directly to mongo database?
Logstash has a dedicated MongoDB output plugin. So you could send the data from Filebeat to Logstash which sends it to your MongoDB (this approach is not direct but a valid workaround).
A Jobber Docker container (running periodic tasks) outputs on stdout, which is captured by Filebeat (with Docker containers autodiscovery flag on) and then sent to Logstash (within an ELK stack) or to Elasticsearch directly.
Now on Kibana, the document looks as such:
#timestamp Jan 20, 2020 # 20:15:07.752
...
agent.type filebeat
container.image.name jobber_jobber
...
message {
"job": {
"command":"curl http://my.service/run","name":"myperiodictask",
"status":"Good",
"time":"0 */5 * * * *"
},
"startTime":1579540500,
"stdout":"{\"startDate\":\"2020-01-20T16:35:00.000Z\",\"endDate\":\"2020-01-20T17:00:00.000Z\",\"zipped\":true,\"size\":3397}",
"succeeded":true,
"user":"jobberuser",
"version":"1.4"
}
...
Note: above 'message' field is a simple string reflecting a json object; above displayed format is for clearer readability.
My goal is to be able to request Elastic on the message fields, so I can filter by Jobber tasks for instance.
How can I make that happen ?
I know Filebeat uses plugins and the container tags to apply this or that filter: are there any for Jobber? If not, how to do this?
Even better would be to be able to exploit the fields of the Jobber task result (under the 'stdout' field)! Could you please direct me to ways to implement that?
Filebeat provides processors to handle such tasks.
Below's a configuration to handle the needs "Decode the json in the 'message' field", "Decode the json in the 'stdout' within" (both using the decode_json_fields processor), and other Jobber-related needs.
Note that given example filter the events going through Filebeat by a 'custom-tag' label given to the Docker container hosting the Jobber process. The docker.container.labels.custom-tag: jobber condition should be replaced according to your usecase.
filebeat.yml:
processors:
# === Jobber events processing ===
- if:
equals:
docker.container.labels.custom-tag: jobber
then:
# Drop Jobber events which are not job results
- drop_event:
when:
not:
regexp:
message: "{.*"
# Json-decode event's message part
- decode_json_fields:
when:
regexp:
message: "{.*"
fields: ["message"]
target: "jobbertask"
# Json-decode message's stdout part
- decode_json_fields:
when:
has_fields: ["jobbertask.stdout"]
fields: ["jobbertask.stdout"]
target: "jobbertask.result"
# Drop event's decoded fields
- drop_fields:
fields: ["message"]
- drop_fields:
when:
has_fields: ["jobbertask.stdout"]
fields: ["jobbertask.stdout"]
The decoded fields are placed in the "jobbertask" field. This is to avoid index-mapping collision on the root fields. Feel free to replace "jobbertask" by any other field name, keeping care of mapping collisions.
In my case, this works whether Filebeat addresses the events to Logstash or to Elasticsearch directly.
I have below cloudwatch alarm defined in CF template for altering me on queries running for 30 mins or more.
Type: AWS::CloudWatch::Alarm
Properties:
AlarmName: !Sub "awsredshift-${RSClusterName}-QueryDuration"
AlarmDescription: Redshift QueryDuration Alarm
Namespace: AWS/Redshift
MetricName: QueryDuration
Dimensions:
- Name: ClusterIdentifier
Value: !Ref RSClusterName
- Name: latency
Value: long
ActionsEnabled: true
AlarmActions:
- !Ref TopicARN
OKActions:
- !Ref TopicARN
ComparisonOperator: GreaterThanOrEqualToThreshold
DatapointsToAlarm: 1
EvaluationPeriods: 1
Period: 300
Statistic: Average
Threshold: 1800000000
TreatMissingData: missing
But its activating the alarms when there are no queries running that long, am I missing something?
Also is there any way to customize the alarms to put logic in them, I would like to get the SQL text of the query which is running longer. Is there any way to do this via cloudwatch alarms? If not whats the best way to do it - probably lambda?
An alternative approach you could use is to implement a Query Monitoring Rule in Redshift for queries where query_execution_time exceeds 30 minutes and uses the log action to record the details of the query in the STL_WLM_RULE_ACTION table.
This captures all the info you might need about long running queries but doesn't create an alert. However, it's easy enough to set something up yourself to do that, Amazon provide an example solution using Lambda here.
I'm using salt for my deployment issues and have the following question.
Is there any mechanism to retry a command?
For instance I have some thing like this:
platform_deps_git:
git.latest:
- name: ...
- rev: master
- target: ...
- user: ...
- identity: ...
But sometimes the network may fail. Is there any way to retry platform_deps_git instruction?
The next version of Salt (2014.7.0) will have an "onfail" requisite. This will allow you to take another action if something fails.
The docs are here:
http://docs.saltstack.com/en/latest/ref/states/requisites.html#onfail
What I do is grep through salt output whenever I run a highstate and if it sees any failures I rerun the highstate.
There's a first-class retry mechanism for states that was added in 2017:
platform_deps_git:
git.latest:
- name: ...
- rev: master
- target: ...
- user: ...
- identity: ...
- retry:
attempts: 5
until: True
interval: 60
splay: 10
The retry option supports a few different options for controlling its behavior.