HDFS port 8020 not accessible from outside.

[#1]

Followed all the instructions to set up the Hadoop 3.0 cluster and Ambari 2.7. HDFS port not accessible from outside.

1. The output of "netstat -tulapn | grep 8020 " from inside the server

tcp 0 0 127.0.1.1:8020 0.0.0.0:* LISTEN 11892/java

tcp 0 0 127.0.1.1:8020 127.0.0.1:52128 ESTABLISHED 11892/java

tcp 0 0 127.0.0.1:55998 127.0.1.1:8020 TIME_WAIT -

tcp 0 0 127.0.0.1:52128 127.0.1.1:8020 ESTABLISHED 11608/java

tcp 0 0 127.0.0.1:56118 127.0.1.1:8020 ESTABLISHED 13891/java

tcp 0 0 127.0.1.1:8020 127.0.0.1:56118 ESTABLISHED 11892/java

2. The output of "nc -zv mighadoop01.mydomain 8020" from outside.

nc: connectx to mighadoop01.mydomain port 8020 (tcp) failed: Connection refused

3. The output of "nc -zv mighadoop01.mydomain 8020" from inside the server.

Connection to mighadoop01.mydomain 8020 port [tcp/*] succeeded!

4. Server's /etc/hosts file

127.0.0.1localhost localhost.localdomain

::1ip6-localhost ip6-loopback

172.31.16.140mighadoop01 mighadoop01.mydomain

Any pointers would be much appreciated.

[#2]

Not sure if this is helpful. But, netstat on say port 9000, seems to deliver different results.

netstat -tulapn | grep 9000

Output:

tcp        0      0 172.31.16.140:40174     172.31.16.140:9000      TIME_WAIT   -
tcp6       0      0 :::9000                 :::*                    LISTEN      11114/java
tcp6       0      0 172.31.16.140:9000      172.31.16.140:40180     TIME_WAIT   -
tcp6       0      0 172.31.16.140:9000      172.31.16.140:40176     TIME_WAIT   -
tcp6       0      0 172.31.16.140:9000      172.31.16.140:40178     TIME_WAIT   -

[#3]

Don't Write 127.0.0.1 node01 in your hosts file,Write 192.168.3.5 instead