Set dfs.namenode.accesstime.precision from Ambari in HDP-2.2

[#1]

PROBLEM:

The dfs.namenode.accesstime.precision value cannot be set from Ambari 2.1.0 when using the HDP-2.2 stack.

Symptoms include:

Searching for this config using the 'Filter...' box from Ambari shows 'No properties to display.'

Adding the property to 'Custom hdfs-site' (in the 'Add Property' popup) tells the user that 'This property is already defined'.

Attempts at clicking on the 'Find property' link again says 'No properties to display.'

The property is visible on all cluster nodes in /etc/hadoop/conf/hdfs-site.xml but it is set to 0.

Trying to edit this property manually on each node only reverts the setting back to 0 whenever the HDFS is restarted.

ROOT CAUSE:

Known bug:

https://issues.apache.org/jira/browse/AMBARI-13006

https://hortonworks.jira.com/browse/BUG-43478

Ambari 2.1.0 added the ability to manage HDFS NFS Gateway settings, but, this only works for HDP stacks running at version 2.3.0 and higher.

RESOLUTION:

A fix will be included in Ambari 2.1.2.

WORKAROUND:

Ambari's configs.sh script will allow users to adjust the dfs.namenode.accesstime.precision property. The syntax is below:

/var/lib/ambari-server/resources/scripts/configs.sh -u AMBARI_USER -p AMBARI_PASS set AMBARI_HOST CLUSTER_NAME hdfs-site dfs.namenode.accesstime.precision "<VALUE>" 

Substitute AMBARI_USER, AMBARI_PASS, AMBARI_HOST, CLUSTER_NAME and VALUE with appropriate values for the environment in use. For example:

/var/lib/ambari-server/resources/scripts/configs.sh -u admin -p admin set ambarinode.example.com examplecluster hdfs-site dfs.namenode.accesstime.precision "360000"

KEYWORDS / TAGS: ambari dfs.namenode.accesstime.precision configs.sh