NameNode is not leaving safemode and is not getting up. Need help.

[#1]

I'm using Ambari 2.2.1.0 and HDP 2.3.4.0

Using Ambari UI, I tried to start my NN. But, its showing below error.

safemode: Call From server1.ddns.net/141.178.0.16 to server1.ddns.net:8020 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused 2016-06-03 12:40:06,640 - Retrying after 10 seconds. Reason: Execution of '/usr/hdp/current/hadoop-hdfs-namenode/bin/hdfs dfsadmin -fs hdfs://server1.ddns.net:8020 -safemode get | grep 'Safe mode is OFF'' returned 1. safemode: Call From server1.ddns.net/141.178.0.16 to server1.ddns.net:8020 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused

After that, I tried below commands and the outputs are:

[root@server1 ~]# sudo -u hdfs hdfs dfsadmin -report
report: Call From server1.ddns.net/141.178.0.16 to server1.ddns.net:8020 failed on connection exception: java.net.ConnectException: Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused

[root@server1 ~]# sudo -u hdfs hdfs dfsadmin -safemode enter
safemode: Call From server1.ddns.net/141.178.0.16 to server1.ddns.net:8020 failed on connection exception: java.net.ConnectException: Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused

[root@server1 ~]# sudo -u hdfs hdfs dfsadmin -safemode leave
safemode: Call From server1.ddns.net/141.178.0.16 to server1.ddns.net:8020 failed on connection exception: java.net.ConnectException: Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused

[root@server1 ~]# 

1) Why is it not leaving from safemode?

2) What could be the solution to resolve my problem and make the NN up?

Please help me in this regard....

[#2]

Not sure why NN format required here.

[#3]

@c pat....I couldnt find the namenode location...

[#4]

I did first two step but I got the same connection refused when I tried 777 rights

[#5]

Please Add this below lines to hdfs-site.xml in between configuration properties and restart the hdfs.

<property>

<name>dfs.safemode.threshold.pct</name>

<value>0</value>

</property>

[#6]

@PRAFUL DASH

Thanks it works for me.

[#7]

Hello, I am facing the same error in my cluster, and same all above thing is reflecting, how did you solve this problem. waiting for your reply. please heal me out. @c pat