Monitoring Application server

[Mani]

Hi All,
This is my first post in Zabbix. And i need to know some information on Zabbix. Can i know How zabbix detects whether an application server like weblogic or websphere is currently Up or Down ?? What is the mechanism that Zabbix uses? Its difficult to trace out the code since files are huge.
It would be helpful if u say me the mechanism.
Thanks,
mani.

[elkor]

well it depends on what you tell it to do.

it could check to see if the process is running, check to make sure a tcp connection could be made, you could even write a script to connect to the application server and verify the contents of the reply.

It's open-ended.

[James Wells]

Greetings,

I created a simple check for Weblogic, perhaps it might be useful to you;

UserParameter=custom[weblogicconsole],wget -q -T 1 -t 1  http://localhost:7011/console -O /dev/null ; echo $?

This entry goes into your zabbix_agentd.conf file on the client, changing the port number to what ever you choose.

[Mani]

Piece of code execcution !!

Dear James,
Is that piece of code run by the "agent" in that system where the application server runs ?? And if it is, How the agent(The piece of code) Checks it ?? Can i have some insight on that piece of code given by you ??

It would be good since i am new to this tool.

Thanks for ur replies
Mani.

[James Wells]

Dear James,
Is that piece of code run by the "agent" in that system where the application server runs ?? And if it is, How the agent(The piece of code) Checks it ?? Can i have some insight on that piece of code given by you ??

With Zabbix 1.1, you have the ability to create custom items / probes. After creating the items, you simply restart the agent. Once this is done, you go back to the server and create a item / poll for it.

In the case of this snippet, when the server asks the agent for the item called 'custom[weblogicconsole]', the agent will execute the command 'wget -q -T 1 -t 1 http://localhost:7011/console -O /dev/null ; echo $?' which returns an error code inidicating success or failure. The server then stores that error code and processes it as you configure it to.

Please note that I am using 'localhost' in the URL, however, you could just as easily use the FQDN of the application server, or it's real IP address as long as the application server is allowing connections to that address.

Also note, that I am specifying a port in the URL section, that part may changes based on your configuration.

[Mani]

Thanks James

Thank you james,
That was a nice explanation. And i will just say in my understanding as follows::
The Zabbix server polls the agents which would run in all the servers(to be monitored) where the applications are hosted. Once it is issued, all the agents give the reply to the server. Am i correct ?? If i am wrong please do correct me !! That was just an abstract view and i am now in the learining phase.

Thanks again,
Mani.

[James Wells]

Thank you james,
That was a nice explanation. And i will just say in my understanding as follows::
The Zabbix server polls the agents which would run in all the servers(to be monitored) where the applications are hosted. Once it is issued, all the agents give the reply to the server. Am i correct ?? If i am wrong please do correct me !! That was just an abstract view and i am now in the learining phase.

That's correct. One thing that may cause some confusion, is that the Agents only run the command when they are specifically asked to by the server. So it does not hurt to have this custom item on systems where it will never get run.

[Mani]

Thanks James

Dear James,
Thanks and this provides me confidence to go ahead.
Mani..