Hive replication policy definition JSON file

The policy definition JSON file contains all the parameters required to create a Hive replication policy. When you edit the file to define a Hive replication policy, remove the parameters that are not required for the replication policy.

Parameters in Hive replication policy definition JSON file

The following table lists the parameters in the policy definition JSON file that are required for a Hive replication policy:


Parameter	Description
name	Enter the unique name for the policy.
type	Enter HIVE to create a Hive replication policy.
mapReduceService	Enter the MapReduce or YARN service for the replication policy to use.
logPath	Enter an alternate path for the logs, if required.
replicationStrategy	Enter STATIC or DYNAMIC to determine whether the file replication tasks should be distributed among the mappers statically or dynamically. The default is DYNAMIC. Static replication distributes file replication tasks among the mappers up front to achieve an uniform distribution based on the file sizes. Dynamic replication distributes the file replication tasks in small sets to the mappers, and as each mapper completes its tasks, it dynamically acquires and processes the next unallocated set of tasks.
skipChecksumChecks	Enter true to skip checksum checks. The default is true. Checksums are used to perform the following tasks: To skip replication of files that have already been copied. When set to true, the replication job skips copying a file if the file lengths and modification times are identical between the source and destination clusters. Otherwise, the job copies the file from the source to the destination. To redundantly verify the integrity of data. However, checksums are not required to guarantee accurate transfers between clusters. HDFS data transfers are protected by checksums during transfer and storage hardware also uses checksums to ensure that data is accurately stored. These two mechanisms work together to validate the integrity of the copied data.
skipListingChecksumChecks	Enter true to skip checksum check while comparing two files to determine whether they are the same or not. Otherwise, the file size and last modified time are used to determine if files are the same or not. Skipping the check improves performance during the mapper phase. note If you set skipChecksumChecks to false, the skipListingChecksumChecks is also set to false by default.
abortOnError	Enter true to stop the policy job when an error occurs. This ensures that the files copied up to that point remain on the destination, but no additional files are copied. The default is false.
abortOnSnapshtDiffFailures	Enter true to stop the replication job if a snapshot diff fails during replication.
preserve	Enter true to preserve the block size, replication count, permissions (including ACLs), and extended attributes (XAttrs) as they exist on the source file system. blockSize replicationCount permissions extendedAtrributes Enter false to use the settings as configured on the destination file system. By default, the source system settings are preserved.
deletePolicy	Enter one of the following options: KEEP_DELETED_FILES - Retains the destination files even when they no longer exist at the source. This is the default option. DELETE_TO_TRASH - Moves files to the trash folder if the HDFS trash is enabled. (Not supported when replicating to S3 or ADLS.) DELETE_PERMANENTLY - Uses the least amount of space; use with caution.
alert	Configure the following parameters as required: onFailure - Enter true to generate alerts when the replication job fails. onStart - Enter true to generate alerts when the replication job starts. onSuccess - Enter true to generate alerts when the replication job completes successfully. onAbort - Enter true to generate alerts when the replication job is aborted.
exclusionFilters	Enter one or more directory paths to exclude from replication.
databasesAndTables	database - Enter one or more database names to include in replication. tablesIncludeRegex - Enter one or more regular expression-based paths to tables to include in replication. For example, if you enter `table1\|table2\|table3`, Replication Manager includes the specified tables for replication. If you enter `DB:db_name Table: (?!table1\|table2\|table3).+`, Replication Manager includes all the tables in the 'db_name' database and excludes 'table1', 'table2', and 'table3' from replication. tablesExcludeRegex is a legacy option. You can enter one or more regular expression-based paths of tables to exclude in replication.
sentryPermissions	Enter INCLUDE to import both Hive object and URL permissions.
skipUrlPermissions	Enter true to import only the Hive object permissions.
numThreads	Enter the number of threads to use during replication.
frequencyInSec	Auto-populated after the policy runs successfully. Shows the time duration between two replication jobs in seconds.
targetDataset	Auto-populated after the policy runs successfully. Shows the target location where the replicated files are available on the target cluster.
cloudCredential	Enter the cloud credentials.
sourceCluster	Shows the source cluster name.
targetCluster	Shows the target cluster name in the dataCenterName$cluster name format. For example, "DC-US$My Destination 17".
startTime	Shows the start time of the replication job in the YYYY-MM-DDTHH:MM:SSZ format.
endTime	Shows the end time of the replication job in the YYYY-MM-DDTHH:MM:SSZ format.
distcpMaxMaps	Enter the maximum map slots to limit the number of map slots per mapper. The default value is 20.
distcpMapBandwidth	Enter the maximum bandwidth to limit the bandwidth per mapper. The default is 100 MB.
queueName	Enter the YARN queue name if not set to Default queue name. By default, the Default queue name is used.
tdeSameKey	Enter true if the source and destination are encrypted with the same TDE key.
description	Enter a description for the policy.
enableSnapshotBasedReplication	Enter true to enable snapshot-based replication.
cloudEncryptionAlgorithm	Enter the cloud encryption algorithm.
cloudEncryptionKey	Enter the cloud encryption key.
plugins	Enter the plugins to deploy on all the nodes in the cluster if you have multiple repositories configured in your environment.
hiveExternalTableBaseDirectory	Enter the Hive external table base directory path.
cmPolicySubmitUser	Enter the following options: userName - Enter the user name that you are using to run the policy. sourceUser - Enter the source cluster username, if any.

Sample Hive replication policy definition JSON file

The following snippet shows the contents of the Hive replication policy definition JSON file. While editing the file, ensure that you remove the key-value pairs that are not required for the Hive replication policy.

{
	"name": "string",
	"type": "HIVE",
	"sourceDataset": {
		"hdfsArguments": {
			"path": "string",
			"mapReduceService": "string",
                     "logPath": "string",
                     "replicationStrategy": "DYNAMIC"|"STATIC",
			"errorHandling": {
				"skipChecksumChecks": true|false,
				"skipListingChecksumChecks": true|false,
				"abortOnError": true|false,
				"abortOnSnapshotDiffFailures": true|false
			},
			"preserve": {
				"blockSize": true|false,
				"replicationCount": true|false
				"permissions": true|false,
				"extendedAttributes": true|false
			},
			"deletePolicy": "KEEP_DELETED_FILES"|"DELETE_TO_TRASH"|"DELETE_PERMANENTLY",
			"alert": {
				"onFailure": true|false,
				"onStart": true|false,
				"onSuccess": true|false,
				"onAbort": true|false
			},
			"exclusionFilters": ["string", ...]
			},
			"hiveArguments": {
				"databasesAndTables": [
					{
						"database": "string",
						"tablesIncludeRegex": "string",
						"tablesExcludeRegex": "string",
					}
					...
				],
				"sentryPermissions": "INCLUDE"|"EXCLUDE",
				"skipUrlPermissions": true|false,
				"numThreads": integer
			}
		},
		"frequencyInSec": integer,
		"targetDataset": "string",
		"cloudCredential": "string",
		"sourceCluster": "string",
		"targetCluster": "string",
		"startTime": "string",
		"endTime": "string",
		"distcpMaxMaps": integer,
		"distcpMapBandwidth": integer,
		"queueName": "string",
		"tdeSameKey": true|false,
		"description": "string",
		"enableSnapshotBasedReplication": true|false
		"cloudEncryptionAlgorithm": "string",
		"cloudEncryptionKey": "string",
		"plugins": ["string", ...],
		"hiveExternalTableBaseDirectory": "string",
		"cmPolicySubmitUser": {
			"userName": "string",
			"sourceUser": "string"
		}
	}