How to identify process id for a server (for example, Oracle Service Bus) that is listening on port number, say 8090

Young WebLogic/JBoss application server administrators in my company have asked me one question on several occasions - "There are several Java processes running in the Unix server. How do I identify the process id of an application server (for example, Oracle Service Bus) listening on port number 8090". I thought this tip may be required by many others in other parts of the world and hence this post.

In Linux:
It is little straight forward to find out the process id by using the following command.


[portalmid@SVRCBS59 ~]$ netstat -anp | grep 8090
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
tcp 0 0 ::ffff:172.20.31.59:8090 :::* LISTEN 21962/java
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:39995 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:47691 ESTABLISHED 21962/java
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:42816 ESTABLISHED 21962/java
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:40047 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:48227 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:39825 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:52100 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:45243 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:44991 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:38068 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:33974 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:36778 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:55202 ESTABLISHED 21962/java
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:59590 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:57827 FIN_WAIT2 -
tcp 0 0 ::ffff:172.20.31.59:8090 ::ffff:172.20.31.60:43493 ESTABLISHED 21962/java
[portalmid@SVRCBS59 ~]$

Needless to explain, the process id is 21962.


In Solaris:
The above command does not work as such. I will write another post with example. Please wait for further update on this.

Thanks for reading my post and request you please to leave your comment here.

Linux - How much swap memory should I need?

Always, you will encounter a typical question - how much memory should be allocated to swap memory? Should it be same as the size of RAM, twice the size of RAM or else? This blog is not a tutorial on swap memory but a tip on its size.

Earlier recommendations (in the era of smaller size RAM) maintained that one should use swap memory which is twice the size of the RAM. It does not hold good anymore. You needed more swap memory because the size of RAM was small. But, now-a-days, you don't need to rely on swap memory for your (large) memory requirement when adequate RAM is cheaply available. If you have a large RAM that is sufficient to support your applications, then dependency on the swap memory reduces a lot (if not eliminated completely).

See blow recommendation from RedHat.

Amount of RAM in the system	Recommended swap space	Recommended swap space if allowing for hibernation
⩽ 2GB	2 times the amount of RAM	3 times the amount of RAM
> 2GB – 8GB	Equal to the amount of RAM	2 times the amount of RAM
> 8GB – 64GB	0.5 times the amount of RAM	1.5 times the amount of RAM
> 64GB	4GB of swap space	No extra space needed

Read the following articles for more information.
https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Installation_Guide/s2-diskpartrecommend-ppc.html#id4394007

https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Storage_Administration_Guide/ch-swapspace.html

ERROR 1130 (HY000): Host 'hostname' is not allowed to connect to this MySQL server

By default, My SQL server does not allow remote access to the database, but often this is a requirement when you run your web/application server and database in two different machines.

You will have to put some extra work to make it working. The magic is that you will have to provide access to the client machine from which you are trying to access the remote server. While it may not be great  idea to provide root access to a client machine, this one will allow your client machine quickly to connect to the database server.

Here you go for step by step guide: -

Step1 : Log on to your remote mysql database server: mysql -u root -p
Step 2: Run the command to use mysql schema: use mysql
Step 3: Run the command to provide access: GRANT ALL ON *.* to 'root'@'<client-hostname or IP address>' IDENTIFIED BY '<your password>'
Ste 4: Run the command: flush PRIVILEGES

The above will allow you to access your database remotely.

Sometime, you may get an error "ERROR 1045 (28000): Access denied for user 'root'@'hostname' (using password: YES)". It is mostly due to an incorrect password.

Oracle SOA BPEL Exception Handling - WSDL messageType "{http://schemas.oracle.com/bpel/extension}remoteFault" of variable "" is not defined in any of the WSDL files

Exception handling is an essential requirement while building any robust application. It is true for the application that is built using BPEL also. As you would know, Oracle BPEL supports both business specific exceptions (they are declared in the service WSDL) and run time exceptions (Needless to say, they are NOT declared in the WSDL). This post is about supporting run time exception.

Assume that as part of your BPEL flow, you are invoking a SOAP service that is hosted remotely. When the remote service is not up and running, then BPEL flow will send back a fault to the client. The fault message will be something similar to the following: -

<env:Envelope xmlns:env="http://schemas.xmlsoap.org/soap/envelope/">
   <env:Header/>
   <env:Body>
      <env:Fault>
         <faultcode>env:Server</faultcode>
         <faultstring>oracle.fabric.common.FabricInvocationException: Unable to access the following endpoint(s): http://localhost:9090/axis2/services/StockQuoteService.StockQuoteServiceHttpSoap11Endpoint/</faultstring>
         <faultactor/>
         <detail>
            <exception>Unable to access the following endpoint(s): http://localhost:9090/axis2/services/StockQuoteService.StockQuoteServiceHttpSoap11Endpoint/</exception>
         </detail>
      </env:Fault>
   </env:Body>
</env:Envelope>

This is not a correct behaviour for a good application. The application should catch the exceptions and handle it properly depending on the application requirement. Assume that, in this case, you have to return a default value, say -1, instead of sending exception message.

Oracle BPEL supports this by having 'Add Catch' construct which can be added to the 'Scope' construct where in you actually have defined the 'Invoke' activity. In Oracle SOA suite 11g, when you add 'Catch' construct, it will import a WSDL (namely RuntimeFault.wsdl) that defines the structure of the runtime message automatically. The definition is as given below: -

<?xml version="1.0" encoding="UTF-8"?>
<definitions name="RuntimeFault"
             targetNamespace="http://schemas.oracle.com/bpel/extension"
             xmlns:xsd="http://www.w3.org/2001/XMLSchema"
             xmlns="http://schemas.xmlsoap.org/wsdl/">

    <message name="RuntimeFaultMessage">
        <part name="code" type="xsd:string"/>
        <part name="summary" type="xsd:string"/>
        <part name="detail" type="xsd:string"/>
    </message>
</definitions>

The above message will support catching code, summary and details of the remote exception thrown because of the downtime of the remote service. In this example, we are not going to use any of these three parts (however, it is possible to do that). Alternatively, we are going to catch the exception and return a default value, say -1.

When you define the 'Catch' construct, it will add a line as given below in your .bpel file: -

<variable messageType="bpelx:remoteFault" name="FaultVar"/>

- where FaultVar is the name of the fault variable using which you can  access its child elements - code, summary and detail


After adding Catch construct, now do a 'Deploy' to application server. But you will get an error as given below: -

Error(67): WSDL messageType "{http://schemas.oracle.com/bpel/extension}remoteFault" of variable "" is not defined in any of the WSDL files

So, what went wrong?

Take a look at these two :-
a) FaultVar variable declaration in the bpel file and
b) RuntimeFaultMessage message definition in the RuntimeFault.wsdl.

The FaultVar is of 'bpelx:remoteFaul' type which is not defined anywhere. Instead, RuntimeFault.wsdl defines another messgae type which is of "RuntimeFaultMessage" type. So, solution is simple - just replace 'remoteFault' by 'RuntimeFaultMessage'. It will do the necessary MAGIC!!!

Now, recompile and deploy to application server. The BPEL service will get deployed onto the application server. When you access the service, now you will get the expected response

<env:Envelope xmlns:env="http://schemas.xmlsoap.org/soap/envelope/" xmlns:wsa="http://www.w3.org/2005/08/addressing">
   <env:Body>
      <processResponse xmlns="http://xmlns.oracle.com/StockApps/StockMarket/StockMarketProcess">
         <result>-1</result>
      </processResponse>
   </env:Body>
</env:Envelope>

Hope this is useful to you.

Happy Fault Handling!

Oracle Business Rules error - Fact not found in the rule engine working memory, rule session execution failed

Recently, I got stuck with the a problem while I was learning Oracle Business Rules. Many of you would have faced this very same issue.

Fact not found in the rule engine working memory, rule session execution failed.
The rule session 60015 failed because an instance of the fact com.oracle.xmlns.rules.insuranceeligibility.ApplicantOutput could not be found in the working memory of the rule session.
This is most likely a rule modeling error. The decision service interaction expects the fact instance to exist in the working memory of the rule session. Check the rule actions in rule designer and make sure that a fact of the expected type is being asserted. If the error persists, contact Oracle Support Services. 60015

I am not intending to create a OBR tutorial page as there several good websites/blogs already available. Herewith I am including only the necessary details.

Please refer to the ruleset which I have created in JDeveloper editor.

There could be several reasons why you got this error. After hours of investigation, I 'accidentally' found the root cause - I have not defined 'else' condition in my rule set. Please find below the modified ruleset.

After the rule modification, now every thing seems to be working fine. Hope this tip will be useful in saving your valuable time. Here is the full BPEL flow for your reference.