Error connecting to Cassandra - com.datastax.driver.core.exceptions.InvalidQueryException
by Dhillon, Manjot
Hello, I am trying to start hawkular services, version hawkular-1.0.0.Alpha13-SNAPSHOT.
As per the documentation, I am using Cassandra version 3.0.12. On starting the hawkular service, I see the following error -
33m01:58:08,209 WARN [org.hawkular.alerts.engine.impl.CassDefinitionsServiceImpl] (Thread-239 (ActiveMQ-client-global-threads-15127043)) Could not connect to Cassandra cluster - assuming is not up yet. Cause: com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: apsrd6612.uhc.com/10.204.85.28:9042 (com.datastax.driver.core.exceptions.InvalidQueryException: unconfigured table schema_keyspaces))
The cassandra driver included with the hawkular service - cassandra-driver-core-2.2.0-rc3.jar, which may be causing the issue.
Thanks,
Manjot
This e-mail, including attachments, may include confidential and/or
proprietary information, and may be used only by the person or entity
to which it is addressed. If the reader of this e-mail is not the intended
recipient or his or her authorized agent, the reader is hereby notified
that any dissemination, distribution or copying of this e-mail is
prohibited. If you have received this e-mail in error, please notify the
sender by replying to this message and delete this e-mail immediately.
4 hours, 8 minutes
essay
by Dana Daster
I needed to write an essay on career goals for scholarships but I just didn't understand how to do it on my own. I had never written an essay before and I was no good at it. So I found information about that career goal essay for scholarships https://essayservice.com/blog/guide-on-career-goals-essay website and it came in handy for me. Because I immediately understood how to do it. So I wrote a great essay thanks to this article
5 hours, 3 minutes
MasterPapers
by Kyle Linel
Want excellent performance of your academic assignments? You should contact https://www.masterpapers.com/, whose works are always unique and undergo a thorough check for plagiarism. In addition, all services are provided in complete confidentiality - your personal data and order details will remain protected. The site ensures that each client receives not only high-quality work, but also maximum satisfaction from interaction with the service and will be able to order more.
3 days, 12 hours
major change in the way we will have to monitor domain mode
by John Mazzitelli
I'm looking at how domain mode monitoring is going to work now that we are moving toward the Prometheus / jmx-exporter way of doing things.
Turns out, due to the way WildFly domain mode exposes things via JMX (rather, I should say, *doesn't* expose things) compared to DMR, I think we are going to have to require the hawkular agent to be deployed to all slave servers, in addition to the master host controller.
In domain mode, you can access all the child slave servers (the individual servers in all server groups) via the host controller's DMR tree - so we only needed one agent on the host controller to monitor the domain. For example, to see a metric for a deployment on "server-one" that is managed by host controller "master", I can simply ask the host controller for it:
/host=master/server=server-one/deployment=test-simple-1.0.0.war/subsystem=undertow/:read-attribute(name=active-sessions)
{
"outcome" => "success",
"result" => 0
}
The nice thing about WildFly's management DMR interface is that the domain mode tree is identical to the standalone tree with the exception that on the host controller, you simply prepend the host/server identifiers to the DMR path. So, for a standalone WildFly, a DMR path for the active-sessions metric for my test-simple application would be:
/deployment=test-simple-1.0.0.war/subsystem=undertow/:read-attribute(name=active-sessions)
If I want to ask the host controller to give me the exact same metric from that server, I simply prepend the host/server name in the DMR path:
/host=master/server=server-one/deployment=test-simple-1.0.0.war/subsystem=undertow/:read-attribute(name=active-sessions)
The agent has knowledge of this pattern; knowing this pattern we can cleverly configure the metadata so we can share types across domain and standalone for inventory discovery.
The problem: WildFly does not expose its JMX MBeans in an equally clever way. I do not see MBeans that provide metrics for the slave servers.
For example, in JMX, I see WildFly host controller has this MBean:
jboss.as:host=master,server=server-one
Looks very analogous to the DMR resource named /host=master/server=server-one resource ... right??
Well, there are no deployments associated with this MBean. You would think (following the DMR pattern) that there would be an MBean named:
jboss.as:host=master,server=server-one,deployment=test-simple-1.0.0.war
But there is not. Nor is there:
jboss.as:host=master,server=server-one,deployment=test-simple-1.0.0.war,subsystem=undertow
which is where you would expect that server's web subsystem metrics to be (if it were to follow the same DMR pattern). But, again, this doesn't exist.
I can't find JMX MBeans for anything related to the individual slave servers (not just deployments).
In short, I do not believe the Prometheus JMX Exporter can be used to collect metrics for all slave servers in a domain if that JMX Exporter is simply installed on a host controller. This is because the host controller's JMX MBeans do not expose metric data for individual slave servers.
We would have to have our agent in each slave server (which are just standalone servers - so the agent would be as if it is monitoring a standalone server). We could have an agent in the host controller, too, but it would only be responsible for monitoring/managing the host controller itself.
[this message was sent on Tuesday, November 21, 2017 at 10:11 PM EST]
1 month, 1 week
Hawkular Metrics 0.13.0 - Release
by Stefan Negrea
Hello Everybody,
I am happy to announce release 0.13.0 of Hawkular Metrics. This release is anchored by Hawkular integration enhancements, under-the-cover refactorings and fixes, and a new bulk data generation tool.
Here is a list of major changes in this release:
1) Data Generation Tool
* A new tool that generates bulk metrics data to be used in performance and load testing.
* It generates directly Cassandra data files (SSTables), which leads to a very fast generation process for large amounts of metrics data.
* For more details: https://github.com/hawkular/hawkular-metrics/tree/master/data-generator (HWKMETRICS-355)
2) Receive Metrics via Hawkular Bus
* When deployed within Hawkular distribution, the project now accepts metrics via the Hawkular Bus; until now only the REST API had support for Metrics insertion.
* Hawkular Metrics currently support publishing of newly inserted metrics to the bus and receiving metrics via the bus.
* For more details: HWKMETRICS-347, HWKMETRICS-352
3) Sorted Stacked Metrics Results
* When requesting stacked metrics aggregation the results are now ordered (HWKMETRICS-353)
4) External Integrations
* Heapster sink now divides storing to multiple calls. This is an improvement over the initial implementation that had one REST API call per metric (HWKMETRICS-290)
* ptrans now works with a Hawkular Metrics instance protected by Hawkular Accounts via Hawkular distribution (HWKMETRICS-342)
* Grafana integration via Influxdb compatible end-point allows connections to a Hawkular Metrics instance protected by Hawkular Accounts via Hawkular distribution (HWKMETRICS-343)
Github Release:
https://github.com/hawkular/hawkular-metrics/releases/tag/0.13.0
JBoss Nexus Maven artifacts:
http://origin-repository.jboss.org/nexus/content/repositories/public/org/...
Jira release tracker:
https://issues.jboss.org/browse/HWKMETRICS/fixforversion/12329530
Hawkular Metrics Clients
* Ruby: https://github.com/hawkular/hawkular-client-ruby
* Python: https://github.com/hawkular/hawkular-client-python
* Go: https://github.com/hawkular/hawkular-client-go
A big "Thank you" goes to John Sanda, Thomas Segismont, Mike Thompson, Matt Wringe, Michael Burman, and Heiko Rupp for their project contributions.
Thank you,
Stefan Negrea
Software Engineer
2 months, 1 week
Nursing Research Proposal
by Nursing Writer
For those embarking on research endeavors in nursing, Nursing Writing Services offers a valuable resource at https://www.nursingwritingservices.com/research-proposal/. Their expertise in crafting well-structured research proposals tailored to the complexities of healthcare ensures thorough preparation for academic and professional pursuits. With a focus on clarity, methodology, and adherence to academic standards, their service facilitates the development of compelling research proposals essential for advancing knowledge in nursing practice and education.
2 months, 2 weeks
