Known Issues in MapReduce and YARN

Learn about the known issues in MapReduce and YARN, the impact or changes to the functionality, and the workaround.

Known Issues

COMPX-14820: Delete Queue and its Children throws "Queue capacity was reduced to zero, but failed to delete queue."
When trying to perform the operation "Delete Queue and its Children" on a queue that has one or more siblings, the operation fails as YARN has some constraints. If the queue performing the operation "Delete Queue and its Children" is a leaf node, then the operations succeeds.
COMPX-13177: QueueManager webapp requests fail with 'HTTP ERROR 400 Unsupported ciphersuite TLS_EDH_RSA_WITH_3DES_EDE_CBC_SHA'
Products: Cloudera Manager for CDP Private Cloud Base Cloudera Manager for CDP Public Cloud Context: Centos 7.8 and Redhat 7.8 operating systems, when FIPS support is enabled. Problem: When attempting to display the Yarn Queue Manager interface, Cloudera Manager displays an error: "HTTP ERROR 400 Unsupported ciphersuite TLS_EDH_RSA_WITH_3DES_EDE_CBC_SHA". Workarounds: Edit the file /etc/default/cloudera-scm-server. Around line 28, modify the line that starts with "#export CMF_OVERRIDE_TLS_CIPHERS=..." Remove the comment mark "#" Remove all ciphers with "3DES" in the name. Save the file. Re-start the Cloudera Manager Server service.
CDPD-56559: MapReduce jobs can intermittently fail during a rolling upgrade.
During a rolling upgrade between versions 7.1.9 and 7.1.9, MapReduce jobs may fail with message, RuntimeException: native snappy library not available. Although the native Snappy compression library is not loaded, a checkmark displays to indicate that the Snappy compression library is loading for NodeManagers that are pending upgrades. This causes the MapReduce jobs that are associated with the NodeManagers to fail. After the upgrade, the jobs work as expected. This issue only impacts rolling upgrades from before 7.1.9 to a higher version.
COMPX-12021 Queue Manager configurations on Scheduler Configuration page are not working
When setting the following properties on the YARN Queue Manager UI, the properties are set in capacity-scheduler.xml which does not have any effect on YARN. The properties need to be set in yarn-site.xml, which does not happen when you set them through YARN Queue Manager.
  • "Maximum Application Priority" – "yarn.cluster.max-application-priority"
  • "Enable Monitoring Policies" – "yarn.resourcemanager.scheduler.monitor.enable"
  • "Monitoring Policies" – "yarn.resourcemanager.scheduler.monitor.policies"
  • "Preemption: Observe Only" – "yarn.resourcemanager.monitor.capacity.preemption.observe_only"
  • "Preemption: Monitoring Interval (ms)" – "yarn.resourcemanager.monitor.capacity.preemption.monitoring_interval"
  • "Preemption: Maximum Wait Before Kill (ms)" – "yarn.resourcemanager.monitor.capacity.preemption.max_wait_before_kill"
  • "Preemption: Total Resources Per Round" – "yarn.resourcemanager.monitor.capacity.preemption.total_preemption_per_round"
  • "Preemption: Over Capacity Tolerance" – "yarn.resourcemanager.monitor.capacity.preemption.max_ignored_over_capacity"
  • "Preemption: Maximum Termination Factor" – "yarn.resourcemanager.monitor.capacity.preemption.natural_termination_factor"
  • "Enable Intra Queue Preemption" – "yarn.resourcemanager.monitor.capacity.preemption.intra-queue-preemption.enabled"
  1. In Cloudera Manager, select the YARN service.
  2. Click the Configuration tab.
  3. Search for yarn-site.xml.
  4. Under YARN Service Advanced Configuration Snippet (Safety Valve) for yarn-site.xml, add the corresponding parameter and value you need.
  5. Click Save Changes.
  6. Restart the YARN services.
COMPX-11380 Queue Manager displays an error stating that it is unable to complete a request
If Queue Manager incorrectly detects an inactive Resource Manager, it displays an error stating that it is unable to complete a request.
Refresh the browser and reload the YARN Queue Manager UI.
COMPX-6214: When there are more than 600 queues in a cluster, potential timeouts occur due to performance reasons that are visible in the Configuration Service.
The Cloudera Manager proxy timeout configuration field is added now. This issue is tracked in OPSAPS-60554. For this release, the timeout is increased from 20 seconds to 5 minutes. However, if this problem occurs, Cloudera recommends you to increase the proxy timeout value.
COMPX-5817: Queue Manager UI will not be able to present a view of pre-upgrade queue structure. CM Store is not supported and therefore Yarn will not have any of the pre-upgrade queue structure preserved.
When a Data Hub cluster is deleted, all saved configurations are also deleted. All YARN configurations are saved in CM Store and this is yet to be supported in Data Hub and Cloudera Manager. Hence, the YARN queue structure also will be lost when a Data Hub cluster is deleted or upgraded or restored.
COMPX-6628: Unable to delete single leaf queue assigned to a partition.

In the current implementation, you cannot delete a single leaf queue assigned to a partition.

For each non-default partition, perform the following for the single child leaf queue and its parent queues:
  1. In Cloudera Manager, click Cluster > YARN.
  2. Click the Configuration tab.
  3. Search for ResourceManager. In the Filters pane, under Scope, select ResourceManager.
  4. Add the following in Capacity Scheduler Configuration Advanced Configuration Snippet (Safety Valve):
    Name: yarn.scheduler.capacity.<queuePath>.accessible-node-labels.<partition>.capacity
    Value: 0

    Set the value to 0 in Percentage mode, and 0w in Weight mode, and [memory=0,vcores=0] in Absolute mode.

    Name: yarn.scheduler.capacity.<queuePath>.accessible-node-labels.<partition>.maximum-capacity  
    Value: 100

    Set the value to 100 in Percentage and Weight mode and [memory=0,vcores=0] in Absolute mode.

  5. Adjust the capacities of the siblings of the parent queue for the same partition.
  6. Click Save Changes.
  7. Restart the active ResourceManager service for the changes to apply.
  8. In Cloudera Manager, click Cluster > YARN Queue Manager UI.
  9. Delete the desired single child leaf queue.
COMPX-5240: Restarting parent queue does not restart child queues in weight mode
When a dynamic auto child creation enabled parent queue is stopped in weight mode, its static and dynamically created child queues are also stopped. However, when the dynamic auto child creation enabled parent queue is restarted, its child queues remain stopped. In addition, the dynamically created child queues cannot be restarted manually through the YARN Queue Manager UI either.
Delete the dynamic auto child creation enabled parent queue. This action also deletes all its child queues, both static and dynamically created child queues, including the stopped dynamic queues. Then recreate the parent queue, enable the dynamic auto child creation feature for it and add any required static child queues.
COMPX-5589: Unable to add new queue to leaf queue with partition capacity in Weight/Absolute mode
  1. User creates one or more partitions.
  2. Assigns a partition to a parent with children
  3. Switches to the partition to distribute the capacities
  4. Creates a new child queue under one of the leaf queues but the following error is displayed:
Error :
2021-03-05 17:21:26,734 ERROR 
com.cloudera.cpx.server.api.repositories.SchedulerRepository: Validation failed for Add queue 
operation. Error message: CapacityScheduler configuration validation 
Failed to re-init queues : Parent queue 'root.test2' have children queue used mixed of  weight 
mode, percentage and absolute mode, it is not allowed, please double check, details:
{Queue=root.test2.test2childNew, label= uses weight mode}. {Queue=root.test2.test2childNew, 
label=partition uses percentage mode}             
To create new queues under leaf queues without hitting this error, perform the following:
  1. Switch to Relative mode
  2. Create the required queues
  3. Create the required partitions
  4. Assign partitions and set capacities
  5. Switch back to Weight mode
  1. Create the entire queue structure
  2. Create the required partitions
  3. Assign partition to queues
  4. Set partition capacities
COMPX-5264: Unable to switch to Weight mode on creating a managed parent queue in Relative mode
In the current implemention, if there is an existing managed queue in Relative mode, then conversion to Weight mode is not be allowed.
To proceed with the conversion from Relative mode to Weight mode, there should not be any managed queues. You must first delete the managed queues before conversion. In Weight mode, a parent queue can be converted into managed parent queue.
COMPX-5549: Queue Manager UI sets maximum-capacity to null when you switch mode with multiple partitions
If you associate a partition with one or more queues and then switch the allocation mode before assigning capacities to the queues, an Operation Failed error is displayed as the max-capacity is set to null.

After you associate a partition with one or more queues, in the YARN Queue Manager UI, click Overview > <Partition name> from the dropdown list and distribute capacity to the queues before switching allocation mode or creating placement rules.

COMPX-4992: Unable to switch to absolute mode after deleting a partition using YARN Queue Manager
If you delete a partition (node label) which has been associated with queues and those queues have capacities configured for that partition (node label), the CS.xml still contains the partition (node label) information. Hence, you cannot switch to absolute mode after deleting the partition (node label).
It is recommended not to delete a partition (node label) which has been associated with queues and those queues have capacities configured for that partition (node label).
COMPX-1445: Queue Manager operations are failing when Queue Manager is installed separately from YARN
If Queue Manager is not selected during YARN installation, Queue Manager operation are failing. Queue Manager says 0 queues are configured and several failures are present. That is because ZooKeeper configuration store is not enabled.
  1. In Cloudera Manager, select the YARN service.
  2. Click the Configuration tab.
  3. Find the Queue Manager Service property.
  4. Select the Queue Manager service that the YARN service instance depends on.
  5. Click Save Changes.
  6. Restart all services that are marked stale in Cloudera Manager.
COMPX-1451: Queue Manager does not support multiple ResourceManagers
When YARN High Availability is enabled there are multiple ResourceManagers. Queue Manager receives multiple ResourceManager URLs for a High Availability cluster. It picks the active ResourceManager URL only when Queue Manager page is loaded. Queue Manager cannot handle it gracefully when the currently active ResourceManager goes down while the user is still using the Queue Manager UI.
Reload the Queue Manager page manually.
COMPX-3329: Autorestart is not enabled for Queue Manager in Data Hub
In a Data Hub cluster, Queue Manager is installed with autorestart disabled. Hence, if Queue Manager goes down, it will not restart automatically.
If Queue Manager goes down in a Data Hub cluster, you must go to the Cloudera Manager Dashboard and restart the Queue Manager service.
Third party applications do not launch if MapReduce framework path is not included in the client configuration
MapReduce application framework is loaded from HDFS instead of being present on the NodeManagers. By default the mapreduce.application.framework.path property is set to the appropriate value, but third party applications with their own configurations will not launch.
Set the mapreduce.application.framework.path property to the appropriate configuration for third party applications.
JobHistory URL mismatch after server relocation
After moving the JobHistory Server to a new host, the URLs listed for the JobHistory Server on the ResourceManager web UI still point to the old JobHistory Server. This affects existing jobs only. New jobs started after the move are not affected.
For any existing jobs that have the incorrect JobHistory Server URL, there is no option other than to allow the jobs to roll off the history over time. For new jobs, make sure that all clients have the updated mapred-site.xml that references the correct JobHistory Server.
CDH-49165: History link in ResourceManager web UI broken for killed Spark applications
When a Spark application is killed, the history link in the ResourceManager web UI does not work.
To view the history for a killed Spark application, see the Spark HistoryServer web UI instead.
CDH-6808: Routable IP address required by ResourceManager
ResourceManager requires routable host:port addresses for yarn.resourcemanager.scheduler.address, and does not support using the wildcard address.
Set the address, in the form host:port, either in the client-side configuration, or on the command line when you submit the job.
YARN cannot start if Kerberos principal name is changed
If the Kerberos principal name is changed in Cloudera Manager after launch, YARN will not be able to start. In such case the keytabs can be correctly generated but YARN cannot access ZooKeeper with the new Kerberos principal name and old ACLs.
There are two possible workarounds:
  • Delete the znode and restart the YARN service.
  • Use the reset ZK ACLs command. This also sets the znodes below /rmstore/ZKRMStateRoot to world:anyone:cdrwa which is less secure.
Queue Manager does not open on using a custom user with a default Kerberos principal
If a custom user is used with the default Kerberos principal, the Queue Manager web UI displays an HTTP ERROR 400 error.
Ensure that the Queue Manager process_username property matches the YARN process_username property.
COMPX-8687: Missing access check for getAppAttemps
When the Job ACL feature is enabled using Cloudera Manager (YARN > Configuration > Enablg JOB ACLproperty), the mapreduce.cluster.acls.enabled property is not generated to all configuration files, including the yarn-site.xml configuration file. As a result the ResourceManager process will use the default value of this property. The default property of mapreduce.cluster.acls.enabled is false.
Workaround: Enable the Job ACL feature using an advanced configuration snippet:
  1. In Cloudera Manager select the YARN service.
  2. Click Configuration.
  3. Find the YARN Service MapReduce Advanced Configuration Snippet (Safety Valve) property.
  4. Click the plus icon and add the following:
    • Name: mapreduce.cluster.acls.enabled
    • Value: true
  5. Click Save Changes.
COMPX-7493: YARN Tracking URL that is shown in the command line does not work when knox is enabled
When Knox is configured for YARN, the Tracking URL printed in the command line of an YARN application such as spark-submit shows the direct URL instead of the Knox Gateway URL.
Upgrade CDP Runtime to CDP 7.1.9 CHF 2, and then you need to perform the following steps:
  1. Open the Cloudera Manager Admin Console and go to the Knox service.
  2. Click on the Knox Gateway Home URL.
  3. Copy the YARN Resource Manager Web UI V2 URL from the Knox Gateway Home page.

    For example,

  4. Open the Cloudera Manager Admin Console and go to the YARN service.
  5. Click the Configuration tab and search for resourcemanager_config_safety_valve.
  6. Add the Resource Manager Advanced Configuration Snippet (Safety Valve) for yarn-site.xml property, and specify its value by using the YARN Resource Manager Web UI V2 URL, copied earlier, as follows:
    Name: yarn.web-proxy.gateway.url
    Value: <YARN Resource Manager Web UI V2 URL>
  7. Enter a Reason for Change and then click Save Changes.
  8. Restart YARN.

Unsupported Features

The following YARN features are currently not supported in Cloudera Data Platform:
  • Application Timeline Server v2 (ATSv2)
  • Auxiliary Services
  • Container Resizing
  • Distributed or Centralized Allocation of Opportunistic Containers
  • Distributed Scheduling
  • Docker on YARN (DockerContainerExecutor) on Data Hub clusters
  • Fair Scheduler
  • GPU support for Docker
  • Hadoop Pipes
  • Moving jobs between queues
  • Native Services
  • Pluggable Scheduler Configuration
  • Queue Priority Support
  • Reservation REST APIs
  • Resource Estimator Service
  • Resource Profiles
  • (non-Zookeeper) ResourceManager State Store
  • Rolling Log Aggregation
  • Shared Cache
  • YARN Federation