how to modify dfs.permissions.superusergroup in HDP 2.6.3

[#1]

hi

I cannot find dfs.permissions.superusergroup via ambari (HDFS-->config) in HDP 2.6.3

When I search "dfs.permissions" I see only the parameter "dfs.permissions.enabled"

If i try to add it to the custom hdfs-site I get "Line 1: Property "dfs.permissions.superusergroup" is already defined in this configuration file"

Checking on the local file system I do see that the parameter exists but I cannot modify it via ambari.

I have cluster with HDP 2.6.1 and it is modifiable there.

OS is RHEL 7.3

Any help will be appriciated.

Thanks

[#2]

To me, this seems to be a bug. I tried to report it against Ambari:

https://issues.apache.org/jira/browse/AMBARI-22839

Maybe it is related to this fix?

https://issues.apache.org/jira/browse/AMBARI-22086

[#3]

Is there a workaround for this problem, which doesn't involve upgrade/downgrade?

[#4]

@Poojan Khanpara

Here is what I got from HDP experts:
Work-around:

1. Edit /var/lib/ambari-server/resources/common-services/HDFS/x.x.x.x.x/configuration/hdfs-site.xml

2. Modify the XML for commenting the <property-type>GROUP</property-type> tag. Like this:

<property>
<name>dfs.permissions.superusergroup</name>
<value>hdfs</value>
<!-- <property-type>GROUP</property-type> -->
<description>The name of the group of super-users.</description>
<on-ambari-upgrade add="true"/>
</property>


3. Restart Ambari
ambari-server restart

[#5]

That worked, thanks! Now I can see the option on the ambari UI.

[#6]

I am assuming the above change wouldn't survive future Ambari upgrade.