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"dfs.namenode.http-address.mycluster.nn1":
"%HOSTGROUP::hostmaster_group_1%:50070"
This property value is interpreted by the Blueprint processor to refer to the host that maps to the “host“master_group_1” host group, which should include a “NAMENODE” among its list of components. The address property listed above should map to the host for “host“master_group_1”, at the port “50070”.
Using this syntax is the most portable way to define host-specific properties within a Blueprint, since no direct host name references are used. This will allow a Blueprint to be applied in a wider variety of cluster deployments, and not be tied to a specific set of hostnames.
Please refer to the link below for the full Blueprint example for HDFS NameNode HA:
hdfs_ha_blueprint. json
Register Blueprint with Ambari Server
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