Tomcat not accessible on Amazon EMR

Question

I created amazon EMR cluster with one master and one slave.
I installed Tomcat on my master instance.
I replaced all "8080" with "8686" and "localhost" with "0.0.0.0" in /conf/server.xml.
I started tomcat instance and can see below output of command "netstat -anltp | grep "LISTEN".

tcp        0      0 127.0.0.1:3306          0.0.0.0:*    LISTEN      -               
tcp        0      0 172.31.28.158:22222     0.0.0.0:*    LISTEN      5209/as   
tcp        0      0 172.31.28.158:50000     0.0.0.0:*    LISTEN      5213/as   
tcp        0      0 172.31.28.158:50001     0.0.0.0:*    LISTEN      5210/as   
tcp        0      0 172.31.28.158:50002     0.0.0.0:*    LISTEN      5212/as   
tcp        0      0 172.31.28.158:50003     0.0.0.0:*    LISTEN      5211/as   
tcp        0      0 172.31.28.158:33333     0.0.0.0:*    LISTEN      5213/as   
tcp        0      0 0.0.0.0:22              0.0.0.0:*    LISTEN      -               
tcp6       0      0 :::8443                 :::*         LISTEN      1478/java       
tcp6       0      0 :::8444                 :::*         LISTEN      1478/java       
tcp6       0      0 :::8321                 :::*         LISTEN      1478/java       
tcp6       0      0 127.0.0.1:8005          :::*         LISTEN      6114/java       
tcp6       0      0 172.31.28.158:9000      :::*         LISTEN      4059/java       
tcp6       0      0 :::8009                 :::*         LISTEN      6114/java       
tcp6       0      0 172.31.28.158:9001      :::*         LISTEN      4098/java       
tcp6       0      0 :::9100                 :::*         LISTEN      4098/java       
tcp6       0      0 :::9101                 :::*         LISTEN      4059/java       
tcp6       0      0 :::8686                 :::*         LISTEN      6114/java       
tcp6       0      0 :::10004                :::*         LISTEN      4734/java       
tcp6       0      0 :::22                   :::*         LISTEN      -

I created security group with inbound "custom TCP rule" for port "8686" to access tomcat instance from outside.
But still I can't access tomcat instance from my local desktop or do "telnet 8686"

Please help.
Thanks.
~Ajit

Answer 1

It's working for all .
Just need to change security group as below.

Inbound 
type          protocol    port range    source   
All TCP       TCP         0 - 65535     0.0.0.0/0

Thanks for all your help.

Answer 2

You should force Tomcat to work with IPv4. Check out the answer here: https://serverfault.com/questions/390840/how-does-one-get-tomcat-to-bind-to-ipv4-address

There's nothing specific to EMR to fix here.