Prerequisites

• HDP 2.0+
• YARN Installed
• At least 2 hosts in the cluster where YARN is not present on 1 host. These steps assume there are 3 hosts in the cluster.

...

1. The yarn-site configuration group (yarn-site.xml) must now be updated to reflect the backup ResourceManager. 
   
   

   property	value
   yarn.resourcemanager.ha.enabled	true
   yarn.resourcemanager.ha.rm-ids	rm1,rm2
   yarn.resourcemanager.hostname.rm1	<rm-host-active>
   yarn.resourcemanager.hostname.rm2	<rm-host-standby>
   yarn.resourcemanager.recovery.enabled	true
   yarn.resourcemanager.store.class	org.apache.hadoop.yarn.server.resourcemanager.recovery.ZKRMStateStore
   yarn.resourcemanager.zk-address	<zk-host-1>, <zk-host-2>, <zk-host-3>
   yarn.resourcemanager.cluster-id	<yarn-cluster-name>
   yarn.resourcemanager.ha.automatic-failover.zk-base-path	/yarn-leader-election

    

    

2. There are two methods to update these configuration properties:
   1. /var/lib/ambari-server/resources/scripts/configs.sh
      
   2. REST API
      
      

3. configs.sh

   Code Block
   $ ./configs.sh set <ambari-server> <cluster-name> yarn-site <param-name> <param-value>   example $ ./configs.sh set c6401.ambari.apache.org cl1 yarn-site yarn.resourcemanager.ha.enabled true

   This will need to be execute for each parameter listed.

    

4. REST API

   1. Get the existing yarn-site configuration version and tag.

      Code Block
      GET http://<ambari-server>/api/v1/clusters/<cluster-name>?fields=Clusters/desired_configs ... { "href" : "http://<ambari-server>/api/v1/clusters/<cluster-name>?fields=Clusters/desired_configs", "Clusters" : { "cluster_name" : "c1", "version" : "HDP-2.1", "desired_configs" : { ... "yarn-site" : { "tag" : "version1", "user" : "_anonymous", "version" : 1 }, ... } } }

   2. Using the value from the tag property of yarn-site, request the current YARN configuration. In this example, <yarn-site-tag> would be "version1".

      Code Block

      GET http://<ambari-server>/api/v1/clusters/<cluster-name>/configurations?(type=yarn-site&tag=<yarn-site-tag>) ... "href" : "http://<ambari-server>/api/v1/clusters/<cluster-name>/configurations?(type=yarn-site&tag=version1)", "items" : [ { "href" : "http://<ambari-server>/api/v1/clusters/<cluster-name>/configurations?type=yarn-site&tag=version1", "tag" : "version1", "type" : "yarn-site", "version" : 1, "Config" : { "cluster_name" : "c1" }, "properties" : { "yarn.acl.enable" : "false", "yarn.admin.acl" : "", ... "yarn.timeline-service.ttl-enable" : "true", "yarn.timeline-service.ttl-ms" : "2678400000", "yarn.timeline-service.webapp.address" : "c6402.ambari.apache.org:8188", "yarn.timeline-service.webapp.https.address" : "c6402.ambari.apache.org:8190" } } ] }

   3. The properties property contains the current yarn-site configuration. Append the new properties to this structure and then update yarn-site.

      Code Block

      PUT http://<ambari-server>/api/v1/clusters/<cluster-name> { "Clusters":{ "desired_config":{ "type":"yarn-site", "tag":"<new-yarn-site-tag>", "properties"::{ "yarn.acl.enable":"false", "yarn.admin.acl":"", ... "yarn.timeline-service.ttl-enable":"true", "yarn.timeline-service.ttl-ms":"2678400000", "yarn.timeline-service.webapp.address":"c6402.ambari.apache.org:8188", "yarn.timeline-service.webapp.https.address":"c6402.ambari.apache.org:8190" ... <yarn-ha-site-properties> "yarn.resourcemanager.ha.enabled": "true",  "yarn.resourcemanager.ha.rm-ids": "rm1,rm2", ... } } } }

5. Restart all stopped services.