This document describes how to configure the services to be deployed on YARN
There are mainly three types of configurations:
Service#configuration
) or component level(Component#configuration
).Configuration#properties
).yarn.service.am-restart.max-attempts
which controls how many times the framework AM can be retried if it fails. These configs are mainly to control the behavior of the framework AM , rather than the custom services launched by the framework.SERVICE_NAME
for referring some system properties.Below describes the details for each type of configurations.
Below is how a configuration object typically looks like:
"configuration" : { "properties" : { "yarn.service.am-restart.max-attempts" : 10 // config for the service AM }, "env" : { // The environment variables to be exported when container gets launched "env1" : "val1" }, "files" : [ // The list of configuration files to be mounted for the container { "type": "HADOOP_XML", // The format of the config file into which the "properties" are dumped "dest_file": "/etc/hadoop/conf/core-site.xml", // The location where the config file is mounted inside the container "properties" : { // The list of key/value pairs to be dumped into the config file "fs.defaultFS" : "hdfs://myhdfs" // This property will be written into core-site.xml } }, { "type": "HADOOP_XML", // The format of the config file. "src_file" : ""hdfs://mycluster/tmp/conf/yarn-site.xml"" // The location of the source config file to be downloaded "dest_file": "/etc/hadoop/conf/yarn-site.xml", // The location where the config file will be mounted inside the container/ "properties" : { "yarn.resourcemanager.webapp.address" : "${COMPONENT_INSTANCE_NAME}.${SERVICE_NAME}.${USER}.${DOMAIN}" // Merge into (or override existing property in) yarn-site.xml } } ] }
dest_file
) to be mounted inside the container. If src_file
is specified, it is also the format for both src_file
and dest_file
.HADOOP_XML : the hadoop xml format. If src_file
is specified, the file content will be read as parsed in hadoop xml format.
XML : the standard xml format
JSON : the standard JSON format
YAML : the YAML format
PROPERTIES : the java PROPERTIES format
TEMPLATE : the plain text format. If src_file
is specified, the content of the src_file
will be written into dest_file
post constant substitution. If src_file
is not specified, use content
as the key in properties
field, and the value will be the actual content to be written in the dest_file
post constant substitution. E.g
{ "type": "TEMPLATE" "dest_file": "/etc/conf/hello" "properties" : { "content" : "Hello world" } }
The string Hello world
will be written into a file located at /etc/conf/hello
inside the container.
src_file
and dest_file
are defined by type
.HADOOP_XML
and TEMPLATE
type.src_file
will be downloaded by YARN NodeManager and be mounted inside the container as in the location specified by dest_file
.properties
field, they are added into (or overwriting existing properties in) the src_file
.src_file
is not specified, only the properties in the properties
field will be written into the dest_file
file.type
. dest_file can be an absolute path or a relative path. If it's a relative path, the file will be located in the $PWD/conf
directory (where $PWD
is the container local directory which is mounted to all docker containers launched by YARN)dest_file
in the format as defined in type
. If src_file
is specified, these properties will be added into (or overwriting existing properties in) the src_file
.This section describes the configurations for configuring the YARN service AM.
These can be specified either in the cluster yarn-site.xml
at the global level or in the properties
field of the Configuration
object as per service basis like below:
{ "configuration" : { "properties" : { "yarn.service.am-restart.max-attempts" : 10 } } }
Above config make the service AM to be retried at max 10 times.
Name | Description |
---|---|
yarn.service.client-am.retry.max-wait-ms | the max retry time in milliseconds for the service client to talk to the service AM. By default, it is set to 0, which means no retry |
yarn.service.client-am.retry-interval-ms | the retry interval in milliseconds for the service client to talk to the service AM. By default, it is 2000, i.e. 2 seconds |
yarn.service.container-failure.retry.max | the max number of retries for the container to be auto restarted if it fails. By default, it is set to -1, which means forever. |
yarn.service.container-failure.retry-interval-ms | the retry interval in milliseconds for the container to be restarted. By default, it is 30000, i.e. 30 seconds |
yarn.service.container-failure.validity-interval-ms | the failure validity interval in milliseconds which when set to a value greater than 0, will not take the failures that happened outside of this interval into failure count. By default, it is set to -1, which means that all the failures so far will be included in failure count. |
yarn.service.am-restart.max-attempts | the max number of attempts for the framework AM |
yarn.service.am-resource.memory | the memory size in GB for the framework AM. By default, it is set to 1024 |
yarn.service.queue | the default queue to which the service will be submitted. By default, it is submitted to default queue |
yarn.service.base.path | the root location for the service artifacts on hdfs for a user. By default, it is under ${user_home_dir}/.yarn/ |
yarn.service.container-failure-per-component.threshold | the max number of container failures for a given component before the AM exits. |
yarn.service.node-blacklist.threshold | Maximum number of container failures on a node before the node is blacklisted by the AM |
yarn.service.failure-count-reset.window | The interval in seconds when the yarn.service.container-failure-per-component.threshold and yarn.service.node-blacklist.threshold gets reset. By default, it is 21600, i.e. 6 hours |
yarn.service.readiness-check-interval.seconds | The interval in seconds between readiness checks. By default, it is 30 seconds |
yarn.service.log.include-pattern | The regex expression for including log files whose file name matches it when aggregating the logs after the application completes. |
yarn.service.log.exclude-pattern | The regex expression for excluding log files whose file name matches it when aggregating the logs after the application completes. If the log file name matches both include and exclude pattern, this file will be excluded. |
yarn.service.rolling-log.include-pattern | The regex expression for including log files whose file name matches it when aggregating the logs while app is running. |
yarn.service.rolling-log.exclude-pattern | The regex expression for excluding log files whose file name matches it when aggregating the logs while app is running. If the log file name matches both include and exclude pattern, this file will be excluded. |
yarn.service.container-recovery.timeout.ms | The timeout in milliseconds after which the service AM releases all the containers of previous attempt which are not yet recovered by the RM. By default, it is set to 120000, i.e. 2 minutes. |
The service framework provides some constant variables for user to configure their services. These variables are either dynamically generated by the system or are static ones such as service name defined by the user. User can use these constants in their configurations to be dynamically substituted by the service AM.E.g.
{ "type" : "HADOOP_XML", "dest_file" : "/etc/hadoop/hbase-site.xml", "properties" : { "hbase.regionserver.hostname": "${COMPONENT_INSTANCE_NAME}.${SERVICE_NAME}.${USER}.${DOMAIN}" } }
Here, COMPONENT_INSTANCE_NAME
and SERVICE_NAME
are the constants to be substituted by the system.
Suppose the COMPONENT_INSTANCE_NAME
is regionserver-0
and SERVICE_NAME
is defined by user as hbase
, user name is devuser
and domain name is dev.test
. Then, the config will be substituted by the service AM and written in the config file /etc/hadoop/hbase-site.xml
inside the container as below:
<property> <name>hbase.regionserver.hostname</name> <value>regionserver-0.hbase.devuser.dev.test</value> </property>
where regionserver-0
is the actual component instance name assigned by the system for this container.
Name | Description |
---|---|
SERVICE_NAME | name of the service defined by the user |
USER | user who submits the service. Note that user name which has “_” will be converted to use “-”, to conform with DNS hostname RFC format which doesn't allow “_”, and all characters will be lowercased E.g. “Bob_dev” will be converted to “bob-dev” |
DOMAIN | the domain name for the cluster |
COMPONENT_NAME | the name for a given component |
COMPONENT_INSTANCE_NAME | the name for a given component instance (i.e. container) |
COMPONENT_ID | the monotonically increasing integer for a given component |
CONTAINER_ID | the YARN container Id for a given container |
${COMPONENT_INSTANCE_NAME}_HOST | the hostname for a component instance (i.e. container), e.g. REGIONSERVER-0_HOST will be substituted by the actual hostname of the component instance. Note all characters must be uppercase. |
${COMPONENT_INSTANCE_NAME}_IP | the ip for a component instance (i.e. container), e.g. REGIONSERVER-0_IP will be substituted by the actual IP address of the component instance. Note all characters must be uppercase. |
CLUSTER_FS_URI | the URI of the cluster hdfs |