Inline.

________________________________
From: Ken Barclay <[email protected]>
Sent: Thursday, July 09, 2015 4:46 PM
To: Siddharth Wagle; Sumit Mohanty
Subject: Re: Can't get Ambari Metrics to write to HDP 2.2.4 HBase

Hi Sid,

Thanks, I can install Phoenix and see how far I get.

Could I understand more about the role HBase is playing in this scenario? Is it 
the case that the Collector needs to create the table schema and so on in 
HBase, but it’s not used in any way once the system is running? And that the 
Collector will take some path I specify in HDFS and use that to write out the 
data? I wanted to use HBase because it’s fast: will HDFS be able to keep up if 
I’m monitoring hundreds of nodes?

AMS data is written to Phoenix Tables in HBASE, in "embedded mode" HBase is 
configured in standalone mode and HBase writes to the local FS.

In "distributed" mode HBase is configured to write to cluster's HDFS. (Note: In 
both cases, I am talking about ams-hbase, the one that Ambari Metrics starts)

In your case you will be utilizing cluster's HBase writing to HDFS, what I 
meant was the ams-hbase will still run because Ambari will start it, just not 
utilized for anything.

I’m just looking for a fast scalable replacement for Ganglia/Nagios that speaks 
HDP and does alerting so I don’t have write all my own HDP alerts in 
Bosun/TSDB. (I’m collecting plenty of HDP metrics currently, but only have a 
handful of alerts set up.)

Metric alerts will be a part of 2.2 and are supported right not for all JMX 
metrics (point in time, more suited to alerts)

In Ambari 2.1, you can add Graphs and visualize any of the metrics collected by 
the backend. 
(https://cwiki.apache.org/confluence/display/AMBARI/Enhanced+Service+Dashboard)

If you are monitoring 1 cluster, you do not have to setup TSDB to visualize 
data with Ambari 2.1

Do you know when the external storage option might be ready?

Not in 2.1, I have a Epic open for 2.2, feel free to leave a comment on the 
Jira, we should get it by 2.2

Thanks for your help
Ken

From: Siddharth Wagle <[email protected]<mailto:[email protected]>>
Date: Thursday, July 9, 2015 at 4:09 PM
To: Sumit Mohanty <[email protected]<mailto:[email protected]>>
Cc: Ken Barclay <[email protected]<mailto:[email protected]>>
Subject: Re: Can't get Ambari Metrics to write to HDP 2.2.4 HBase


Hi Ken,


What you are looking for : "Ambari to use the existing HBase as its datastore 
for metrics", is not the distributed mode.

We envision this to be "external" mode for Ambari Metrics Service where user 
can point to own datastore. It is not currently a supported feature.


"distributed" mode means write to HDFS and do not run HBASE in standalone mode.


Since you are down the path of hacking around this, let me give you some 
pointers. (Theoretically, it should be possible to get this to work)


The Metric Collector runs two processes, 1. embedded HBase and 2. The Collector 
API layer.

Process 2 uses the Phoenix client to create the table schema in HBase.

So you need Phoenix 4.2.0 enabled on your HBase.

The Collector API daemon will look at "hbase.zookeeper.quorum" inside 
/etc/ambari-metrics-collector/conf/hbase-site, and try to connect to it using 
jdbc URL.


Note: Ambari will still start the HBase daemon since external mode is not 
supported yet. If you get everything to work you may just tune down memory 
settings for the embedded HBase and let it run.


Wiki pages should help you with finding out what goes where :

https://cwiki.apache.org/confluence/display/AMBARI/Operations


-Sid


________________________________
From: Sumit Mohanty
Sent: Thursday, July 09, 2015 2:30 PM
To: Siddharth Wagle
Subject: Re: Can't get Ambari Metrics to write to HDP 2.2.4 HBase


FYI​

________________________________
From: Ken Barclay <[email protected]<mailto:[email protected]>>
Sent: Thursday, July 09, 2015 2:27 PM
To: [email protected]<mailto:[email protected]>
Subject: Can't get Ambari Metrics to write to HDP 2.2.4 HBase

Hello,

I’m trying to get Ambari 2.0.1 Monitoring running in our 4-node test cluster in 
a Centos 6 environment. We already have monitoring data coming from OpenTSDB 
(via Bosun) that we’re storing in HBase, and I want Ambari to use the existing 
HBase as its datastore also.

Ambari seems to want to start its own HBase Master, RegionServers, etc, even 
when I try to use ‘distributed’ mode.

I’ve put the Metrics Service operation mode to ‘distributed’, changed 
ams-hbase-site in Ambari to have the right ZK quorum and 
hbase.master.info.bindAddress, and made all the ports the same as for our 
existing HBase. Went down quite the rabbit hole changing znode.parent from 
/hbase to /hbase-unsecure.

On server startup I see the message

15:05:31,160  INFO [main] ZooKeeperRegistry:108 - ClusterId read in ZooKeeper 
is null

Followed by

12:32:47,282  INFO [main] ConnectionManager$HConnectionImplementation:1613 - 
getMaster attempt 25 of 35 failed; retrying after sleep of 20023, 
exception=java.io.IOException: Can't get master address from ZooKeeper; znode 
data == null

Is this a fixable situation? I heard something about Ambari’s distributed 
storage being in ‘technical preview’ but it would be great to get this working.

Thanks
Ken

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