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HDP on Linux – Installation Forum

Error while Installing hosts

  • #16839
    Adam Ocsvari

    Currently I’m using Scientific Linux6 what should be a modified RHEL6.
    When I’m doing the web based install, after the second step, my nodes are installed but not registered.
    I can see 2 things in the log file:
    22:14:14,113 WARN HeartBeatHandler:331 – Received registration request from host with non matching os type, hostname=master, serverOsType=redhat6, agentOstype=scientific6
    ( This is funny, because ALL my servers, also the ambari server are the same scientific6 images)

    But the real problem is maybe this:
    22:36:36,982 WARN nio:651 – Received fatal alert: unknown_ca
    22:36:44,687 WARN nio:651 – null cert chain
    22:36:45,034 WARN nio:651 – handshake alert: no_certificate

    All my servers hase the same hosts file, with fix IP-name pairs. Ping works for everywhere. Also password-less ssh with root.

  • Author
  • #16845

    Hi Adam ,

    I will be happy to help resolve out this issue. Please use FQDN in the Ambari installation process. Ambari server may need to be reset by running the following commands.
    ambari-server stop
    ambari-server reset
    ambari-server start

    Once the Ambari server up , please try to reregister again. If the problem persists take a copy of the error messages and past it here. Hope this helps.


    Adam Ocsvari

    FQDN: All my servers has a hostname-IP matching in the hosts file. ( all file contains all the servers)
    Hostnames: ambari, master, slave
    I did the servers stop,reset,start.. still the same.

    My first message contains all the non-INFO part of the log.
    Here is what the ui displays as log:

    Registration log for master


    Verifying Python version compatibility…
    Using python /usr/bin/python2.6
    Checking for previously running Ambari Agent…
    ERROR: ambari-agent already running
    Check /var/run/ambari-agent/ for PID.
    (‘hostname: ok slave
    ip: ok
    cpu: ok QEMU Virtual CPU version 1.0
    memory: ok 0.97353 GB
    disks: ok
    Filesystem Size Used Avail Use% Mounted on
    27G 1021M 25G 4% /
    tmpfs 499M 0 499M 0% /dev/shm
    /dev/vda1 485M 52M 408M 12% /boot
    193G 2.0G 181G 2% /home/cloud/sshfs
    os: ok Scientific Linux release 6.3 (Carbon)
    iptables: ok
    Chain INPUT (policy ACCEPT 4635 packets, 16M bytes)
    pkts bytes target prot opt in out source destination

    Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
    pkts bytes target prot opt in out source destination

    Chain OUTPUT (policy ACCEPT 5407 packets, 833K bytes)
    pkts bytes target prot opt in out source destination
    selinux: ok SELINUX=disabled
    yum: ok yum-3.2.29-30.el6.noarch
    rpm: ok rpm-4.8.0-27.el6.x86_64
    openssl: ok openssl-1.0.0-27.el6_4.2.x86_64
    curl: ok curl-7.19.7-26.el6_2.4.x86_64
    wget: ok wget-1.12-1.4.el6.x86_64
    net-snmp: UNAVAILABLE
    net-snmp-utils: UNAVAILABLE
    puppet: UNAVAILABLE
    nagios: UNAVAILABLE
    ganglia: UNAVAILABLE
    passenger: UNAVAILABLE
    hadoop: UNAVAILABLE
    yum_repos: ok
    HDP-UTILS- Hortonworks Data Platform Utils Version – HDP-UTILS-1. 52
    zypper_repos: UNAVAILABLE
    ‘, None)
    (‘ File “/usr/lib64/python2.6/”, line 567, in create_connection
    raise error, msg
    error: [Errno 111] Connection refused


    INFO 2013-03-08 08:42:45,442 – SSL Connect being called.. connecting to the server
    INFO 2013-03-08 08:42:45,444 – Unable to connect to: https://ambari:8441/agent/v1/register/slave
    Traceback (most recent call last):
    File “/usr/lib/python2.6/site-packages/ambari_agent/”, line 88, in registerWithServer
    response = self.sendRequest(self.registerUrl, data)
    File “/usr/lib/python2.6/site-packages/ambari_agent/”, line 239, in sendRequest


    Hi Adam,

    What do you get on the hosts when you type "hostname -f". This is what you should enter as the hosts to install to. Also please check that iptables or firewall and selinux are turned off/disabled.


    Adam Ocsvari

    Hi Ted!

    I double checked everything:
    hostname -f correct in every servers.
    SeLinux and IP tables are off everywhere.

    Any other idea?


    Jeff Sposetti

    I think since your agent is return “agentOstype=scientific6”, and that is an unsupported OS, that’s why your agent registration is failing.

    I filed this JIRA for making this logging more informative / less cryptic. If you would like to see supported added for Scientific Linux6, please file a JIRA improvement as well.


    Is there any resolution to this thread? Is there a way to install HDP on SLC6? I got the same problem connecting the Ambari agent and server. I saw the Jira issue for unsupported OS is not resolved.


    INFO 2013-04-30 20:10:17,201 – SSL Connect being called.. connecting to the server
    INFO 2013-04-30 20:10:17,398 – Unable to connect to:
    Traceback (most recent call last):
    File “/usr/lib/python2.6/site-packages/ambari_agent/”, line 89, in registerWithServer
    ret = json.loads(response)
    File “/usr/lib64/python2.6/json/”, line 307, in loads
    return _default_decoder.decode(s)
    File “/usr/lib64/python2.6/json/”, line 319, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
    File “/usr/lib64/python2.6/json/”, line 338, in raw_decode
    raise ValueError(“No JSON object could be decoded”)
    ValueError: No JSON object could be decoded

    Larry Liu

    Hi, Adam and Alex

    I can propose a workaround:

    1. remove any release information under /etc. The file should be like /etc/scientific-release. I am not quite sure.
    2. Create the following 2 files:


    You can copy the content from a redhat version. In my centos 6.0, I have the following content:
    [root@sandbox ~]# cat /etc/redhat-release
    CentOS release 6.3 (Final)
    [root@sandbox ~]# cat /etc/issue
    CentOS release 6.3 (Final)
    Kernel \r on an \m

    Please let me know if it works.


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