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Ambari Server Cannot Add New Host

Ambari Server Cannot Add New Host

Explorer

img-2793-1.jpgI am trying to get Ambari working between 2 hardware machines running the Hortonworks HDP 2.3 sandbox. Both machines can successfully ssh into each other from the terminal without passwords. I am trying to add a new data node (server1.hortonworks.com) to Ambari on the main computer(sandbox.hortonworks.com). I can only assume that the fqdn I am using is correct since everything is working from the terminal. I can successfully ssh server1 When adding the fqdn of server 1 to the main computer along with the private rsa key and then proceeding, it fails and says: Host checks were skipped on 1 hosts that failed to register. I really do not know where to go from here to get the other host added correctly. Please help.

14 REPLIES 14
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Re: Ambari Server Cannot Add New Host

Does the new host have ambari agent already running? If you select to auto-register, Ambari Server will attempt to install it and start it. If it did install the bits, make sure that the /etc/ambari-agent/conf/ambari-agent.ini has the correct FQDN address of the ambari server.

You can also check if the host is already known to Ambari by checking either DB or API. SELECT host_name FROM hosts; http://server:8080/api/v1/hosts/ Once the host is a part of the cluster, it will show up in the ClusterHostMapping table and also

http://server:8080/api/v1/clusters/$name/hosts

Are there any errors in /var/lob/ambari-agent/ambari-agent.log ?

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Re: Ambari Server Cannot Add New Host

Explorer

I have the sandbox and Ambari Server running on both computers while trying to add the new host. how do I find the fqdn of the ambari server? hostname -f ? I will check the log and get bak to you, thanks

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Re: Ambari Server Cannot Add New Host

yes hostname -f.

And if the machines are resolved from both hosts and also, check as subash mentioned about iptables. There is a chance the iptables (firewall is on). /etc/init.d/iptables stop.

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Re: Ambari Server Cannot Add New Host

Explorer

Yes I believe the machines to be resolved, they can ssh from terminal just fine without password. Also I stopped the iptables on both machines and it still was unable to add the host.

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Re: Ambari Server Cannot Add New Host

Super Collaborator

Hi Michael,

Can you please check the iptables and selinux services on the second machine. it they are running please stop that services.

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Re: Ambari Server Cannot Add New Host

Explorer

Sorry I am new to this. I stopped the iptables but how do I check selinux services?

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Re: Ambari Server Cannot Add New Host

Super Collaborator

type the following command in shell as root

getenforce

if the result is enforcing you need to change the configuration in /etc/selinux/config file

SELINUX=disabled

and restart the server once it is done. :)

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Re: Ambari Server Cannot Add New Host

Mentor

@Alejandro Fernandez

there is a list of process to check please see attached doc.

Just to be sure start from checking the network /etc/hosts setup to the end !!

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Re: Ambari Server Cannot Add New Host

Explorer

I followed the pdf you gave precisely,

ntpd is on.

When I get to the page about ntpdate and run the command:ntpdate pool.ntp.org

I get an error that says: Name Server cannot be used:Temporary Failure in name resolution (-3)

any idea what I should do from here? Thank you for your advice

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