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<!-- DO NOT MODIFY THIS FILE DIRECTLY, IT IS AUTO GENERATED BY [org.apache.kyuubi.config.AllKyuubiConfiguration] -->

<div align=center>

![](../imgs/kyuubi_logo.png)

</div>

# Introduction to the Kyuubi Configurations System

Kyuubi provides several ways to configure the system and corresponding engines.


## Environments


You can configure the environment variables in `$KYUUBI_HOME/conf/kyuubi-env.sh`, e.g, `JAVA_HOME`, then this java runtime will be used both for Kyuubi server instance and the applications it launches. You can also change the variable in the subprocess's env configuration file, e.g.`$SPARK_HOME/conf/spark-env.sh` to use more specific ENV for SQL engine applications.
```bash
#!/usr/bin/env bash
#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
#
# - JAVA_HOME               Java runtime to use. By default use "java" from PATH.
#
#
# - KYUUBI_CONF_DIR         Directory containing the Kyuubi configurations to use.
#                           (Default: $KYUUBI_HOME/conf)
# - KYUUBI_LOG_DIR          Directory for Kyuubi server-side logs.
#                           (Default: $KYUUBI_HOME/logs)
# - KYUUBI_PID_DIR          Directory stores the Kyuubi instance pid file.
#                           (Default: $KYUUBI_HOME/pid)
# - KYUUBI_MAX_LOG_FILES    Maximum number of Kyuubi server logs can rotate to.
#                           (Default: 5)
# - KYUUBI_JAVA_OPTS        JVM options for the Kyuubi server itself in the form "-Dx=y".
#                           (Default: none).
# - KYUUBI_NICENESS         The scheduling priority for Kyuubi server.
#                           (Default: 0)
# - KYUUBI_WORK_DIR_ROOT    Root directory for launching sql engine applications.
#                           (Default: $KYUUBI_HOME/work)
# - HADOOP_CONF_DIR         Directory containing the Hadoop / YARN configuration to use.
#
# - SPARK_HOME              Spark distribution which you would like to use in Kyuubi.
# - SPARK_CONF_DIR          Optional directory where the Spark configuration lives.
#                           (Default: $SPARK_HOME/conf)
#


## Examples ##

# export JAVA_HOME=/usr/jdk64/jdk1.8.0_152
# export HADOOP_CONF_DIR=/usr/ndp/current/mapreduce_client/conf
# export KYUUBI_JAVA_OPTS="-Xmx10g -XX:+UnlockDiagnosticVMOptions -XX:ParGCCardsPerStrideChunk=4096 -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:+CMSConcurrentMTEnabled -XX:CMSInitiatingOccupancyFraction=70 -XX:+UseCMSInitiatingOccupancyOnly -XX:+CMSClassUnloadingEnabled -XX:+CMSParallelRemarkEnabled -XX:+UseCondCardMark -XX:MaxDirectMemorySize=1024m  -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=./logs -verbose:gc -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintTenuringDistribution -Xloggc:./logs/kyuubi-server-gc-%t.log -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=10 -XX:GCLogFileSize=5M -XX:NewRatio=3 -XX:MetaspaceSize=512m"
```

For the environment variables that only needed to be transferred into engine side, you can set it with a Kyuubi configuration item formatted `kyuubi.engineEnv.VAR_NAME`. For example, with `kyuubi.engineEnv.SPARK_DRIVER_MEMORY=4g`, the environment variable `SPARK_DRIVER_MEMORY` with value `4g` would be transferred into engine side. With `kyuubi.engineEnv.SPARK_CONF_DIR=/apache/confs/spark/conf`, the value of `SPARK_CONF_DIR` in engine side is set to `/apache/confs/spark/conf`.

## Kyuubi Configurations

You can configure the Kyuubi properties in `$KYUUBI_HOME/conf/kyuubi-defaults.conf`. For example:
```bash
#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

## Kyuubi Configurations

#
# kyuubi.authentication           NONE
# kyuubi.frontend.bind.host       localhost
# kyuubi.frontend.bind.port       10009
#

# Details in https://kyuubi.readthedocs.io/en/latest/deployment/settings.html
```

### Authentication

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.authentication|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>NONE</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Client authentication types.<ul> <li>NOSASL: raw transport.</li> <li>NONE: no authentication check.</li> <li>KERBEROS: Kerberos/GSSAPI authentication.</li> <li>CUSTOM: User-defined authentication.</li> <li>LDAP: Lightweight Directory Access Protocol authentication.</li></ul></div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.authentication<br>\.custom\.class|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>User-defined authentication implementation of org.apache.kyuubi.service.authentication.PasswdAuthenticationProvider</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.3.0</div>
kyuubi\.authentication<br>\.ldap\.base\.dn|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>LDAP base DN.</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.authentication<br>\.ldap\.domain|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>LDAP domain.</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.authentication<br>\.ldap\.guidKey|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>uid</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>LDAP attribute name whose values are unique in this LDAP server.For example:uid or cn.</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.authentication<br>\.ldap\.url|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>SPACE character separated LDAP connection URL(s).</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.authentication<br>\.sasl\.qop|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>auth</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Sasl QOP enable higher levels of protection for Kyuubi communication with clients.<ul> <li>auth - authentication only (default)</li> <li>auth-int - authentication plus integrity protection</li> <li>auth-conf - authentication plus integrity and confidentiality protection. This is applicable only if Kyuubi is configured to use Kerberos authentication.</li> </ul></div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>


### Backend

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.backend\.engine<br>\.exec\.pool\.keepalive<br>\.time|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT1M</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Time(ms) that an idle async thread of the operation execution thread pool will wait for a new task to arrive before terminating in SQL engine applications</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.backend\.engine<br>\.exec\.pool\.shutdown<br>\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT10S</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Timeout(ms) for the operation execution thread pool to terminate in SQL engine applications</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.backend\.engine<br>\.exec\.pool\.size|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>100</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Number of threads in the operation execution thread pool of SQL engine applications</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.backend\.engine<br>\.exec\.pool\.wait\.queue<br>\.size|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>100</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Size of the wait queue for the operation execution thread pool in SQL engine applications</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.backend\.server<br>\.exec\.pool\.keepalive<br>\.time|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT1M</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Time(ms) that an idle async thread of the operation execution thread pool will wait for a new task to arrive before terminating in Kyuubi server</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.backend\.server<br>\.exec\.pool\.shutdown<br>\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT10S</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Timeout(ms) for the operation execution thread pool to terminate in Kyuubi server</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.backend\.server<br>\.exec\.pool\.size|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>100</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Number of threads in the operation execution thread pool of Kyuubi server</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.backend\.server<br>\.exec\.pool\.wait\.queue<br>\.size|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>100</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Size of the wait queue for the operation execution thread pool of Kyuubi server</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>


### Delegation

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.delegation\.key<br>\.update\.interval|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT24H</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>unused yet</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.delegation<br>\.token\.gc\.interval|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT1H</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>unused yet</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.delegation<br>\.token\.max\.lifetime|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT168H</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>unused yet</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.delegation<br>\.token\.renew\.interval|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT168H</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>unused yet</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>


### Engine

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.engine<br>\.connection\.url\.use<br>\.hostname|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>true</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>When true, engine register with hostname to zookeeper. When spark run on k8s with cluster mode, set to false to ensure that server can connect to engine</div>|<div style='width: 30pt'>boolean</div>|<div style='width: 20pt'>1.3.0</div>
kyuubi\.engine<br>\.deregister\.exception<br>\.classes|<div style='width: 65pt;word-wrap: break-word;white-space: normal'></div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>A comma separated list of exception classes. If there is any exception thrown, whose class matches the specified classes, the engine would deregister itself.</div>|<div style='width: 30pt'>seq</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.engine<br>\.deregister\.exception<br>\.messages|<div style='width: 65pt;word-wrap: break-word;white-space: normal'></div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>A comma separated list of exception messages. If there is any exception thrown, whose message or stacktrace matches the specified message list, the engine would deregister itself.</div>|<div style='width: 30pt'>seq</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.engine<br>\.deregister\.exception<br>\.ttl|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT30M</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Time to live(TTL) for exceptions pattern specified in kyuubi.engine.deregister.exception.classes and kyuubi.engine.deregister.exception.messages to deregister engines. Once the total error count hits the kyuubi.engine.deregister.job.max.failures within the TTL, an engine will deregister itself and wait for self-terminated. Otherwise, we suppose that the engine has recovered from temporary failures.</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.engine<br>\.deregister\.job\.max<br>\.failures|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>4</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Number of failures of job before deregistering the engine.</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.engine\.event<br>\.json\.log\.path|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>file:/tmp/kyuubi/events</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The location of all the engine events go for the builtin JSON logger.<ul><li>Local Path: start with 'file:'</li><li>HDFS Path: start with 'hdfs:'</li></ul></div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.3.0</div>
kyuubi\.engine\.event<br>\.loggers|<div style='width: 65pt;word-wrap: break-word;white-space: normal'></div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>A comma separated list of engine history loggers, where engine/session/operation etc events go.<ul> <li>SPARK: the events will be written to the spark history events</li> <li>JSON: the events will be written to the location of kyuubi.engine.event.json.log.path</li> <li>JDBC: to be done</li> <li>CUSTOM: to be done.</li></ul></div>|<div style='width: 30pt'>seq</div>|<div style='width: 20pt'>1.3.0</div>
kyuubi\.engine<br>\.initialize\.sql|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>SHOW DATABASES</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>SemiColon-separated list of SQL statements to be initialized in the newly created engine before queries. This configuration can not be used in JDBC url due to the limitation of Beeline/JDBC driver.</div>|<div style='width: 30pt'>seq</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.engine\.session<br>\.initialize\.sql|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>SHOW DATABASES</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>SemiColon-separated list of SQL statements to be initialized in the newly created engine session before queries. This configuration can not be used in JDBC url due to the limitation of Beeline/JDBC driver.</div>|<div style='width: 30pt'>seq</div>|<div style='width: 20pt'>1.3.0</div>
kyuubi\.engine\.share<br>\.level|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>USER</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Engines will be shared in different levels, available configs are: <ul> <li>CONNECTION: engine will not be shared but only used by the current client connection</li> <li>USER: engine will be shared by all sessions created by a unique username, see also kyuubi.engine.share.level.sub.domain</li> <li>SERVER: the App will be shared by Kyuubi servers</li></ul></div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.engine\.share<br>\.level\.sub\.domain|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Allow end-users to create a sub-domain for the share level of an engine. A sub-domain is a case-insensitive string values in `^[a-zA-Z_]{1,10}$` form. For example, for `USER` share level, an end-user can share a certain engine within a sub-domain, not for all of its clients. End-users are free to create multiple engines in the `USER` share level</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.engine\.single<br>\.spark\.session|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>false</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>When set to true, this engine is running in a single session mode. All the JDBC/ODBC connections share the temporary views, function registries, SQL configuration and the current database.</div>|<div style='width: 30pt'>boolean</div>|<div style='width: 20pt'>1.3.0</div>
kyuubi\.engine\.ui\.stop<br>\.enabled|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>true</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>When true, allows Kyuubi engine to be killed from the Spark Web UI.</div>|<div style='width: 30pt'>boolean</div>|<div style='width: 20pt'>1.3.0</div>


### Frontend

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.frontend<br>\.backoff\.slot\.length|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT0.1S</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Time to back off during login to the frontend service.</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.frontend\.bind<br>\.host|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Hostname or IP of the machine on which to run the frontend service.</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.frontend\.bind<br>\.port|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>10009</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Port of the machine on which to run the frontend service.</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.frontend\.login<br>\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT20S</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Timeout for Thrift clients during login to the frontend service.</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.frontend\.max<br>\.message\.size|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>104857600</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Maximum message size in bytes a Kyuubi server will accept.</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.frontend\.max<br>\.worker\.threads|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>999</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Maximum number of threads in the of frontend worker thread pool for the frontend service</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.frontend\.min<br>\.worker\.threads|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>9</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Minimum number of threads in the of frontend worker thread pool for the frontend service</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.frontend<br>\.worker\.keepalive\.time|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT1M</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Keep-alive time (in milliseconds) for an idle worker thread</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>


### Ha

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.ha\.zookeeper<br>\.acl\.enabled|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>false</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Set to true if the zookeeper ensemble is kerberized</div>|<div style='width: 30pt'>boolean</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.ha\.zookeeper<br>\.connection\.base\.retry<br>\.wait|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>1000</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Initial amount of time to wait between retries to the zookeeper ensemble</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.ha\.zookeeper<br>\.connection\.max<br>\.retries|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>3</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Max retry times for connecting to the zookeeper ensemble</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.ha\.zookeeper<br>\.connection\.max\.retry<br>\.wait|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>30000</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Max amount of time to wait between retries for BOUNDED_EXPONENTIAL_BACKOFF policy can reach, or max time until elapsed for UNTIL_ELAPSED policy to connect the zookeeper ensemble</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.ha\.zookeeper<br>\.connection\.retry<br>\.policy|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>EXPONENTIAL_BACKOFF</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The retry policy for connecting to the zookeeper ensemble, all candidates are: <ul><li>ONE_TIME</li><li> N_TIME</li><li> EXPONENTIAL_BACKOFF</li><li> BOUNDED_EXPONENTIAL_BACKOFF</li><li> UNTIL_ELAPSED</li></ul></div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.ha\.zookeeper<br>\.connection\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>15000</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The timeout(ms) of creating the connection to the zookeeper ensemble</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.ha\.zookeeper<br>\.namespace|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>kyuubi</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The root directory for the service to deploy its instance uri. Additionally, it will creates a -[username] suffixed root directory for each application</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.ha\.zookeeper<br>\.node\.creation\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT2M</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Timeout for creating zookeeper node</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.ha\.zookeeper<br>\.quorum|<div style='width: 65pt;word-wrap: break-word;white-space: normal'></div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The connection string for the zookeeper ensemble</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.ha\.zookeeper<br>\.session\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>60000</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The timeout(ms) of a connected session to be idled</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>


### Kinit

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.kinit\.interval|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT1H</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>How often will Kyuubi server run `kinit -kt [keytab] [principal]` to renew the local Kerberos credentials cache</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.kinit\.keytab|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Location of Kyuubi server's keytab.</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.kinit\.max<br>\.attempts|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>10</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>How many times will `kinit` process retry</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.kinit<br>\.principal|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Name of the Kerberos principal.</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>


### Metrics

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.metrics<br>\.console\.interval|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT5S</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>How often should report metrics to console</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.metrics<br>\.enabled|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>true</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Set to true to enable kyuubi metrics system</div>|<div style='width: 30pt'>boolean</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.metrics\.json<br>\.interval|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT5S</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>How often should report metrics to json file</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.metrics\.json<br>\.location|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>metrics</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Where the json metrics file located</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.metrics<br>\.prometheus\.path|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>/metrics</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>URI context path of prometheus metrics HTTP server</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.metrics<br>\.prometheus\.port|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>10019</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Prometheus metrics HTTP server port</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.metrics<br>\.reporters|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>JSON</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>A comma separated list for all metrics reporters<ul> <li>CONSOLE - ConsoleReporter which outputs measurements to CONSOLE periodically.</li> <li>JMX - JmxReporter which listens for new metrics and exposes them as MBeans.</li>  <li>JSON - JsonReporter which outputs measurements to json file periodically.</li> <li>PROMETHEUS - PrometheusReporter which exposes metrics in prometheus format.</li> <li>SLF4J - Slf4jReporter which outputs measurements to system log periodically.</li></ul></div>|<div style='width: 30pt'>seq</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.metrics\.slf4j<br>\.interval|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT5S</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>How often should report metrics to SLF4J logger</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.2.0</div>


### Operation

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.operation\.idle<br>\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT3H</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Operation will be closed when it's not accessed for this duration of time</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.operation<br>\.interrupt\.on\.cancel|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>true</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>When true, all running tasks will be interrupted if one cancels a query. When false, all running tasks will remain until finished.</div>|<div style='width: 30pt'>boolean</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.operation<br>\.query\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Timeout for query executions at server-side, take affect with client-side timeout(`java.sql.Statement.setQueryTimeout`) together, a running query will be cancelled automatically if timeout. It's off by default, which means only client-side take fully control whether the query should timeout or not. If set, client-side timeout capped at this point. To cancel the queries right away without waiting task to finish, consider enabling kyuubi.operation.interrupt.on.cancel together.</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.operation<br>\.scheduler\.pool|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The scheduler pool of job. Note that, this config should be used after change Spark config spark.scheduler.mode=FAIR.</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.1.1</div>
kyuubi\.operation<br>\.status\.polling<br>\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT5S</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Timeout(ms) for long polling asynchronous running sql query's status</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>


### Session

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.session\.check<br>\.interval|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT5M</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The check interval for session timeout.</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.session\.conf<br>\.ignore\.list|<div style='width: 65pt;word-wrap: break-word;white-space: normal'></div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>A comma separated list of ignored keys. If the client connection contains any of them, the key and the corresponding value will be removed silently during engine bootstrap and connection setup. Note that this rule is for server-side protection defined via administrators to prevent some essential configs from tampering but will not forbid users to set dynamic configurations via SET syntax.</div>|<div style='width: 30pt'>seq</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.session\.conf<br>\.restrict\.list|<div style='width: 65pt;word-wrap: break-word;white-space: normal'></div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>A comma separated list of restricted keys. If the client connection contains any of them, the connection will be rejected explicitly during engine bootstrap and connection setup. Note that this rule is for server-side protection defined via administrators to prevent some essential configs from tampering but will not forbid users to set dynamic configurations via SET syntax.</div>|<div style='width: 30pt'>seq</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.session\.engine<br>\.check\.interval|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT5M</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The check interval for engine timeout</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.session\.engine<br>\.idle\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT30M</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>engine timeout, the engine will self-terminate when it's not accessed for this duration</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.session\.engine<br>\.initialize\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT1M</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>Timeout for starting the background engine, e.g. SparkSQLEngine.</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.session\.engine<br>\.log\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT24H</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>If we use Spark as the engine then the session submit log is the console output of spark-submit. We will retain the session submit log until over the config value.</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.1.0</div>
kyuubi\.session\.engine<br>\.login\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT15S</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The timeout(ms) of creating the connection to remote sql query engine</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.session\.engine<br>\.share\.level|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>USER</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>(deprecated) - Using kyuubi.engine.share.level instead</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.session\.engine<br>\.spark\.main\.resource|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The package used to create Spark SQL engine remote application. If it is undefined, Kyuubi will use the default</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.session\.engine<br>\.startup\.error\.max<br>\.size|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>8192</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>During engine bootstrapping, if error occurs, using this config to limit the length error message(characters).</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.1.0</div>
kyuubi\.session\.idle<br>\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT6H</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>session idle timeout, it will be closed when it's not accessed for this duration</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.session<br>\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>PT6H</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>(deprecated)session timeout, it will be closed when it's not accessed for this duration</div>|<div style='width: 30pt'>duration</div>|<div style='width: 20pt'>1.0.0</div>


### Zookeeper

Key | Default | Meaning | Type | Since
--- | --- | --- | --- | ---
kyuubi\.zookeeper<br>\.embedded\.client\.port|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>2181</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>clientPort for the embedded zookeeper server to listen for client connections, a client here could be Kyuubi server, engine and JDBC client</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.zookeeper<br>\.embedded\.client\.port<br>\.address|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>&lt;undefined&gt;</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>clientPortAddress for the embedded zookeeper server to</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.zookeeper<br>\.embedded\.data\.dir|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>embedded_zookeeper</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>dataDir for the embedded zookeeper server where stores the in-memory database snapshots and, unless specified otherwise, the transaction log of updates to the database.</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.zookeeper<br>\.embedded\.data\.log\.dir|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>embedded_zookeeper</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>dataLogDir for the embedded zookeeper server where writes the transaction log .</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.zookeeper<br>\.embedded\.directory|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>embedded_zookeeper</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The temporary directory for the embedded zookeeper server</div>|<div style='width: 30pt'>string</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.zookeeper<br>\.embedded\.max\.client<br>\.connections|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>120</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>maxClientCnxns for the embedded zookeeper server to limits the number of concurrent connections of a single client identified by IP address</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.zookeeper<br>\.embedded\.max\.session<br>\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>60000</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>maxSessionTimeout in milliseconds for the embedded zookeeper server will allow the client to negotiate. Defaults to 20 times the tickTime</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.zookeeper<br>\.embedded\.min\.session<br>\.timeout|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>6000</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>minSessionTimeout in milliseconds for the embedded zookeeper server will allow the client to negotiate. Defaults to 2 times the tickTime</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.2.0</div>
kyuubi\.zookeeper<br>\.embedded\.port|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>2181</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>The port of the embedded zookeeper server</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.0.0</div>
kyuubi\.zookeeper<br>\.embedded\.tick\.time|<div style='width: 65pt;word-wrap: break-word;white-space: normal'>3000</div>|<div style='width: 170pt;word-wrap: break-word;white-space: normal'>tickTime in milliseconds for the embedded zookeeper server</div>|<div style='width: 30pt'>int</div>|<div style='width: 20pt'>1.2.0</div>

## Spark Configurations

### Via spark-defaults.conf

Setting them in `$SPARK_HOME/conf/spark-defaults.conf` supplies with default values for SQL engine application. Available properties can be found at Spark official online documentation for [Spark Configurations](http://spark.apache.org/docs/latest/configuration.html)

### Via kyuubi-defaults.conf

Setting them in `$KYUUBI_HOME/conf/kyuubi-defaults.conf` supplies with default values for SQL engine application too. These properties will override all settings in `$SPARK_HOME/conf/spark-defaults.conf`

### Via JDBC Connection URL

Setting them in the JDBC Connection URL supplies session-specific for each SQL engine. For example: ```jdbc:hive2://localhost:10009/default;#spark.sql.shuffle.partitions=2;spark.executor.memory=5g```

- **Runtime SQL Configuration**

  - For [Runtime SQL Configurations](http://spark.apache.org/docs/latest/configuration.html#runtime-sql-configuration), they will take affect every time

- **Static SQL and Spark Core Configuration**

  - For [Static SQL Configurations](http://spark.apache.org/docs/latest/configuration.html#static-sql-configuration) and other spark core configs, e.g. `spark.executor.memory`, they will take affect if there is no existing SQL engine application. Otherwise, they will just be ignored

### Via SET Syntax

Please refer to the Spark official online documentation for [SET Command](http://spark.apache.org/docs/latest/sql-ref-syntax-aux-conf-mgmt-set.html)

## Logging

Kyuubi uses [log4j](https://logging.apache.org/log4j/2.x/) for logging. You can configure it using `$KYUUBI_HOME/conf/log4j.properties`.
```bash
#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

# Set everything to be logged to the console
log4j.rootCategory=INFO, console
log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.target=System.err
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss.SSS} %p %c{2}: %m%n

# Set the default kyuubi-ctl log level to WARN. When running the kyuubi-ctl, the
# log level for this class is used to overwrite the root logger's log level.
log4j.logger.org.apache.kyuubi.ctl.ServiceControlCli=ERROR
```

## Other Configurations

### Hadoop Configurations

Specifying `HADOOP_CONF_DIR` to the directory contains hadoop configuration files or treating them as Spark properties with a `spark.hadoop.` prefix. Please refer to the Spark official online documentation for [Inheriting Hadoop Cluster Configuration](http://spark.apache.org/docs/latest/configuration.html#inheriting-hadoop-cluster-configuration). Also, please refer to the [Apache Hadoop](http://hadoop.apache.org)'s online documentation for an overview on how to configure Hadoop.

### Hive Configurations

These configurations are used for SQL engine application to talk to Hive MetaStore and could be configured in a `hive-site.xml`. Placed it in `$SPARK_HOME/conf` directory, or treating them as Spark properties with a `spark.hadoop.` prefix.

## User Defaults

In Kyuubi, we can configure user default settings to meet separate needs. These user defaults override system defaults, but will be overridden by those from [JDBC Connection URL](#via-jdbc-connection-url) or [Set Command](#via-set-syntax) if could be. They will take effect when creating the SQL engine application ONLY.
User default settings are in the form of `___{username}___.{config key}`. There are three continuous underscores(`_`) at both sides of the `username` and a dot(`.`) that separates the config key and the prefix. For example:
```bash
# For system defaults
spark.master=local
spark.sql.adaptive.enabled=true
# For a user named kent
___kent___.spark.master=yarn
___kent___.spark.sql.adaptive.enabled=false
# For a user named bob
___bob___.spark.master=spark://master:7077
___bob___.spark.executor.memory=8g
```

In the above case, if there are related configurations from [JDBC Connection URL](#via-jdbc-connection-url), `kent` will run his SQL engine application on YARN and prefer the Spark AQE to be off, while `bob` will activate his SQL engine application on a Spark standalone cluster with 8g heap memory for each executor and obey the Spark AQE behavior of Kyuubi system default. On the other hand, for those users who do not have custom configurations will use system defaults.
