I have tons of tomcat servers, they are all in a virtual machine. At the moment there is a need to develop a web panel, where I can track the statuses of servers, change their configurations, stop and restart. Actually the question itself: with what technologies can I do this. Previously, there was an idea to use the playbook ansible.
How can I at least display the names of my servers on the page?
There are two standard ways to monitor Tomcat:
you can use Tomcat Manager, especially its text interface,
you can use JMX directly or through the JMX Proxy Servlet. On Tomcat's webpage you can find a not so up-to-date list of MBeans. For some MBeans you'll have to fire up jconsole and explore the names yourself.
Related
I have a java class which manage jobs and execute them via spark(using 1.6).
I am using the API - sparkLauncher. startApplication(SparkAppHandle.Listener... listeners) in order to monitor the state of the job.
The problem is I moved to work in a real cluster environment and this way can’t work when the master and workers are not on the same machine, as the internal implementation is making a use of localhost only (loopback) to open a port for the workers to bind to.
The API sparkLauncher.launch() works but doesn’t let me monitor the status.
What is the best practice for cluster environment using a java code?
I also saw the option of hidden Rest API, is it mature enough? Should I enable it in spark somehow (I am getting access denied, even though the port is open from outside) ?
REST API
In addition to viewing the metrics in the UI, they are also available as JSON. This gives developers an easy way to create new visualizations and monitoring tools for Spark. The JSON is available for both running applications, and in the history server. The endpoints are mounted at /api/v1. Eg., for the history server, they would typically be accessible at http://:18080/api/v1, and for a running application, at http://localhost:4040/api/v1.
More details you can find here.
Every SparkContext launches a web UI, by default on port 4040, that displays useful information about the application. This includes:
A list of scheduler stages and tasks
A summary of RDD sizes and memory usage
Environmental information.
Information about the running executors
You can access this interface by simply opening http://driver-node:4040 in a web browser. If multiple SparkContexts are running on the same host, they will bind to successive ports beginning with 4040 (4041, 4042, etc).
More details you can find here.
I'm looking at using hawtio for our app as a support console. We're not currently using camel or the like, but I am impressed by the ability to connect to remote JVM's via Jolokia/JMX and the logging features and was wondering:
Our use case would be that we have a weblogic server hosting our web app and my thought would be to include hawtio as a war alongside it. In addition to monitoring the web app, we have a number other JVMs running on different servers.
Is it possible to create a dashboard using values from the local JVM, as well as some of the remote JVMs?
Or must one always manually connect to the instance to see the dashboard for that particular JVM?
The current dashboard and JMX plugin does not support that.
Though there is works planned to support gathering statistics from remote JMVs etc. And there is also work on elastichsarch with a kibana web ui.
I need to make an application that runs as a server that accepts connections from various clients and responds to their requests (via proprietary protocol). This server also needs a GUI for configuration and monitoring. I (of course) need to run the server as a service, and the GUI has to be available only at certain moments. Since the server service and GUI share some of the hardware resources and part of the configuration they would run on the same machine. I would like that the GUI and the whole long running service are one process that will run in the background; the GUI would than be invoked (shown) only when needed.
My question is: can this be done with a JavaFX 2 GUI and how?
Thanks in advance
Josip
So you need Monitoring and Management in a Java application? You should be using the Java Management Extensions (JMX) Technology. http://docs.oracle.com/javase/6/docs/technotes/guides/management/overview.html
And if you decide that you can't just use a standard JMX client or create a plugin then you create your JavaFX application as a JMX client.
I work mostly on desktop application on Windows platform. Now I am focusing on Linux platform to host web applications.
While hosting the application on Linux, I don't follow any procedure. I simply CHECKOUT the files from SVN and run the application on home directory. I don't know where to store the application data (example: mysql/postgres or Mongodb or redis, tokyo tyrant). Where to keep the log files.. What is the tip you have when we do the backend maintenance work on the server but display to the user saying that 'maintenance in progress' messages.
How do you host your application on VPS/dedicated/cloud service running Linux application?
Do you have any checklist? Do you have any tips & tricks?
Very broad question
Where do you store application data?. Most people would install MySQL which would properly store the data in /var/lib/mysql and Apache where /var/www is typically used. These applications are usually configured in /etc/apache2 and /etc/mysql.
Where to keep log files?. These almost always goes in to /var/log. For configuration check /etc/syslog.conf
How do you configure a server maintenance message?. Create a HTML file with your message and serve it by configuring apache from /etc/apache2/httpd.conf
How to do virtual Linux servers?. The easiest way is to install an instance on Amazon EC2 or you could use Oracle's VirtualBox (similar to VMWare, but free). You could also try Zen/KVM but these are far form trivial, so unless you have Linux maven around then I would stay clear of these.
I whant to make a web interface on a server that will manage a few dns servers on another servers.
How can i remotely manage a bind dns server programmaticly ?
I would like to add/edit/delete zones.
I see that there is rndc but that only allows reloading of zones and not adding/deleting.
I could NFS mount zones from dns servers and edit them but is there a better way?
If there isn't a hard requirement on writing something like this from scratch, why not simply use an already existing interface without having to reinvent the wheel? A simple Google search for the keywords bind dns web interface yields an entire list of good open source projects in the very first result link.
There is work at the IETF to define a standard for remote control of name servers based on the Netconf framework. See:
https://datatracker.ietf.org/doc/html/draft-ietf-dnsop-name-server-management-reqs
https://datatracker.ietf.org/doc/html/draft-dickinson-dnsop-nameserver-control-00.txt
The requirements include the ability to add/remove zones, etc.
You could set up something that does remote SSH commands? That may be a bit insecure, though, unless the server running the commands themselves is pre-authenticated with an SSH key, and that's the only way you can access the server.