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connection problem

I am very, very sad not to be able to launch my cluster because of a connection problem :(... please find attached a schema where I have tried to explain what are the symptoms...

connection-refused.png

any idea ? (i am sure it's something the configuration...)

Thank you.

Georges.

5 REPLIES 5

Super Mentor

@Georges Colin

May be there are some firewall rules setup mistakenly which is blocking the master1 (50070) port access from master2 host.

Can you please try disabling the FIrewall first to see if disabling the iptables/firewald helps:

# service iptables status
# service iptables stop

(OR)

# systemctl stop firewalld

.

Thank you, Jay, for your answer

unfortunately, i have already stopped the firewall according to the "hortonworks installation" guide... I have successfully intalled HDP but the starting process is blocked due to this "connection refused" problem.

[root@master1 ~]# service iptables stop
Redirecting to /bin/systemctl stop iptables.service
Failed to stop iptables.service: Unit iptables.service not loaded.
[root@master1 ~]# systemctl stop firewalld
[root@master1 ~]# systemctl status firewalld
â firewalld.service - firewalld - dynamic firewall daemon
Loaded: loaded (/usr/lib/systemd/system/firewalld.service; disabled; vendor preset: enabled)
Active: inactive (dead)
Docs: man:firewalld(1)
Jan 02 18:35:36 master1 firewalld[16742]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w2 -w --table filter --d...in?).
Jan 02 18:35:36 master1 firewalld[16742]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w2 -w --table filter --d...name.
Jan 02 18:35:36 master1 firewalld[16742]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w2 -w --table filter --d...name.
Jan 02 18:35:36 master1 firewalld[16742]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w2 -w --table filter --d...in?).
Jan 02 18:35:36 master1 firewalld[16742]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w2 -w --table filter --d...in?).
Jan 02 18:35:36 master1 firewalld[16742]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w2 -w --table filter --d...in?).
Jan 02 18:35:36 master1 firewalld[16742]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w2 -w --table filter --d...in?).
Jan 02 18:35:36 master1 firewalld[16742]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w2 -w --table filter --d...in?).
Jan 08 14:39:16 master1 systemd[1]: Stopping firewalld - dynamic firewall daemon...
Jan 08 14:39:17 master1 systemd[1]: Stopped firewalld - dynamic firewall daemon.
Hint: Some lines were ellipsized, use -l to show in full.
[root@master1 ~]#

sudo netstat -tnpl | grep 50070
tcp 0 0 127.0.0.1:50070 0.0.0.0:* LISTEN 26237/java

It looks like the port 50070 is restricted to local (127.0.0.1) but it should be opened to external access (0.0.0.0). Is there a way to configure this change...

Super Mentor

@Georges Colin

Please login to Ambari UI and then navigate to :

Ambari UI --> HDFS --> Config (Tab) --> Advanced (Sub Tab)

Now on the above Page Just Below to the "Service Actions" Button there is a text files (filter) available please write "dfs.namenode.http-address" there to see the property which should have the address as Hostname (instead of localhost)

Great!... I was unsuccesfully looking for the hdfs-site.xml file... :)... So, now i know configuration are managed through Ambari UI...

Thank you, Jay, it works fine...

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