Ambari DB is damaged without Ambari DB backup - ambari

We have Ambari HDP cluster ( HDP version - 2.6.4 ) , with 420 workers linux machines ( when each worker include data node and node manager service )
Unfortunately Ambari DB is damaged , and we not have Ambari DB dump , so we cant recover Ambari DB , so actually we not have Ambari and Ambari GUI
But HDFS disks on workers machines include HDFS data , and name node is still working with all data as ( journal/hdfsha/current/ ) and ( namenode/current )
So HDFS works without Ambari
So regarding what I said until now - it is possible install new Ambari cluster and then add existing working HDFS to the cluster ?
Dose hortonworks / cloudera have procedure for this process ?

An "Ambari cluster" is not something. You install Ambari agents and point the server at them.
If you wipe the database, then the agents may attempt to reconfigure your services, however, so you better take a backup of at least core-site.xml, hdfs-site.xml, yarn-site.xml, etc.

Related

ambari cluster + poor connection between ambari-agent to ambari server

we have ambari cluster with 872 data-nodes machines , when ambari version is 2.6.x
we have for now some network problem ,
after long investigation we found that , ambari agent that runs on some machine not communicate well with the ambari server
therefore we get some strange behaviors as 5 dead data-nodes from ambari dashboard , while for sure datanodes machine are healthy
is it possible to give more tolerated value in ambari agent configuration so the ack between ambari agent to ambari server will be after more little time in order to ignore the network problems ?
something like timeout or time connection between the ambari agent to ambari server
First of all, you need to get the root cause of the issue why Data Node is showing as Dead.
Ambari agent runs on every node. It is responsible for sending
metrics and heartbeat to the Ambari server which then publishes to
your Ambari web UI.
The name node waits for 10 minutes till it declares the data node as dead and copies
the blocks to other data nodes.
If it's showing that data node is dead then please check the Ambari agent status in
the specific node by running-service ambari-agent status. Parallelly you can check the ambari-agent.log in the worker node to check why Ambari agent stopped working.
You can configure your http timeouts in ambari-agents for service tasks, http timeouts
https://github.com/apache/ambari/blob/trunk/ambari-agent/conf/unix/ambari-agent.ini
There's a HTTP Timeout section you can configure it based on your network throughput.
The file should be in /etc/ambari-agent/ambari.properties

Is it possible to install Apache Ambari on top of an existing cluster

We have an existing Hadoop cluster that is not managed by Ambari. Is it possible to install Apache Ambari on top of an existing Hadoop cluster?
No, Ambari must provision the cluster it's monitoring.
Ambari is designed around a Stack concept where each stack consists of several services. A stack definition is what allows Ambari to install, manage and monitor the services in the cluster.

How to monitor hadoop cluster using Ambari on centos 7

I have a small hadoop cluster i.e one master and three slave nodes. I have to monitor cluster. I have found that we can use Ambari. CentOS 7 is installed on all machines. Please provide a complete details how I can do that ?. I have found that Ambari can be used for new cluster i.e you have to install new cluster. It does not work with already running cluster?
At the moment Ambari does not support CentOS 7, so that's not going to work.
However, Ambari does not perform cluster monitoring on its own. It uses Nagios for the purpose. Nagios is an independent software project that you can setup independently. That said it's kinda painful to do.
ambari-server for Ambari 2.2+ can be installed and works good on CentOS 7.
You have to installed ambari-server on one of the hosts (master node) and can use the webUI hostname:8080 for installing ambari agents on other hosts. Alternatively, ambari agents can be installed manually on other hosts can can be linked to communicate with the ambari-server.

Hadoop Cluster deployment using Apache Ambari

I have listed few queries related to ambari as follows:
Can I configure more than one hadoop cluster via UI of ambari ?
( Note : I am using Ambari 1.6.1 for my hadoop cluster deployment purpose and I am aware that this can be done via Ambari API, but not able to find via ambari portal)
We can check the status of services on each node by “jps” command, if we have configured hadoop cluster w/o ambari.
Is there any way similar to “jps” to check from back end if the setup for hadoop cluster was successful from the backend ?
( Note : I can see that services are showing UP on the ambari portal )
Help Appreciated !!
Please let me know if any additional information is required.
Thanks
The ambari UI is served up by the ambari server for a specific cluster. To configure another cluster you need to point your browser to the URL for that other cluster's ambari server. So you can't see the configuration for multiple servers on the same web page, but you can set browser bookmarks to jump from configuration to configuration.

Datastax OpsCenter not showing nodes

I installed datastax enterprise in my win7 system,but it is not displaying any node in opscenter dashboard.(Actually I have re-installed the datastax due to some issue in previous installation.)
I am getting the node detail in command line using nodetool command,but no node is present in the datastax ops center dashboard.
I think OpsCenter agent is failing to connect the node.
Please help me
Thanks,
Subhra
The agent might not be started on your system in linux its in /usr/share/datastax-agent/bin run the 'install_agent'.
Also check if the ports for running opscenter are not blocked.
Follow below mentioned procedure :
1) Check datastax-agent is installed on nodes and also service is running.
2) Check Port connection is open for datastax-agent.
http://docs.datastax.com/en/archived/opscenter/5.1/opsc/reference/opscPorts_r.html
3) Reconfigure your existing Cluster details in Opscenter, after deleting previous configuration in Opscenter.
4) If issue still exist check log file of opscenter (opscenterd.log)