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WebLogic Interview Questions

In this article I will briefly discuss how I conduct interviews for WebLogic Administration roles.

When conducting interviews I prefer to avoid difficult questions, and instead ask fairly simple questions and look at how well the candidate answers. I would prefer to hire someone who can clearly and concisely explain how to do a simple task than someone who knows every single thing about a particular technology.

I explain at the beginning of the interview, it's acceptable if they are not able to answer every question; I use their answers to help decide if they will be a good fit for the team and the role.

Here are some of the questions I like to ask after I've given them a description of the role on offer.

Non-Technical Questions
  • Which of your previous roles do you think have give you experience that could be important for this role?
  • Tell me what is involved in a typical day in this role?
  • Describe the kind of infrastructure you worked with in this role?
  • On a scale of 1 to 10, with 1 being "no knowledge" and 10 being "know everything", how would you rate your own skills? (I don't look for people who think they "know everything").
  • What are some of the things you need to learn more about?

Technical Questions
  • If you were trying to access an application via a HTTP proxy and were getting a 404 error, how would you go about determining why you were getting this error?
  • Describe how you would go about configuring a WebLogic server to give an application access to a database.
  • How many threads does a managed server make available to an application? (expect different answers for different versions of WebLogic)
  • What kind of problems would you expect to encounter when trying to increase a managed server's maximum heap size to 3 GB? (Problems on 32-bit operating systems).
  • If an application was suffering short periodic freezes, and no errors were appearing in the logs, can you suggest a possible cause? (Garbage collection)
  • How could you prevent these periodic lock-ups?
  • What are the ways you could check when garbage collection is occurring?
  • If you start an admin server as a Windows service, where is that server's classpath defined? (Windows Registry)
  • If you start a managed server via a node manager, where is that server's classpath defined? (config.xml)
  • If a managed server is crashing with a StackOverflow exception, what could be the cause?
  • Describe how you would go about configuring a JMS queue in a WebLogic cluster. (i.e. a distributed queue).
  • Describe how you might run a WLST script?

Other Questions
Note it is also important to ask questions that determine if the candidate is familiar with best practices, such as Change Control and Configuration Management.

Comments

  1. Thanks for sharing this helpful interview questions.

    Interview Questions

    ReplyDelete
  2. do you have more detailed answers to these questions ?

    ReplyDelete
  3. Hi

    I read this post 2 times. It is very useful.

    Pls try to keep posting.

    Let me show other source that may be good for community.

    Source: People manager interview questions

    Best regards
    Jonathan.

    ReplyDelete

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