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ambari host registration failed

New Contributor

I m trying to install HDP 2.6.4 using ambari ambari- in RHEL 7.5 using jdk1.8.0_101 and postgresql-9.5.8. I am able to install ambari agents and ambari server in all hosts. While registering all host in ambari ui all host registration is getting failed except ambari-server host. Also verified /etc/hosts in all servers ,hostname are correct and i am able to telnet the ambari server from all agent servers.

my openssl verion-

openssl version -v

OpenSSL 1.0.2k-fips 26 Jan 2017

I am adding agent log below please check.

INFO 2018-06-11 14:55:42,409 - Connecting to https://amabri_server_host:8440/ca ERROR 2018-06-11 14:55:42,487 - [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:579) ERROR 2018-06-11 14:55:42,487 - SSLError: Failed to connect. Please check openssl library versions. Refer to: for more details. WARNING 2018-06-11 14:55:42,488 - Server at https://amabri_server_host:8440 is not reachable, sleeping for 10 seconds...




Hi @Bhagabati Das,

RHEL 7.5 is not supported for HDP 2.6.4:

However, your error seems to be related to this:


Super Mentor

@Bhagabati Das

If you are using CentOS 7, RHEL7, SLES 12 (Python 2.7) then in order to solve this problem simply configure the Ambari Agent to use TLSv1.2 when communicating with the Ambari Server by editing each Ambari Agent’s "/etc/ambari-agent/conf/ambari-agent.ini" file and adding the following configuration property to the security section:


Then restart the ambari agent:

# ambari-agent restart

For CentOS 6/RHEL6, or SLES 11 (Python 2.6), Edit the file in the JDK being used by the Ambari Server and make the following changes:
Locate the jdk.tls.disabledAlgorithms property and remove the 3DES_EDE_CBC reference
Save the file, and restart the Ambari Server.

More details are available on:

HCC Article:

HCC Thread:

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