by Ramesh Natarajan
on February 5, 2014
When you install PostgreSQL, by default connection to the database using TCP/IP is not allowed.
When you try to connect from a client to a remote PostgreSQL database using psql command, you might get “psql: could not connect to server: Connection refused” error message.
In the following example, from a client machine, we are trying to connect to a PostgreSQL database that is running on 192.168.102.1 server. As you see from the output, it clearly says that the remote PostgreSQL database is not accepting connection.
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by Ramesh Natarajan
on February 4, 2014
I’ll be conducting a hands-on workshop on Linux sysadmin. This will be an one day event with focus on hands-on training. In this all day workshop, you’ll be working on several lab exercises on a Linux system.
This workshop is for newbies or intermediate users of Linux who would like to become proficient in Linux system administration. Wide range of essential sysadmin topics will be covered including package management, user/group management, various security aspects of Linux, filesystem/storage, several networking utilities, monitoring, etc.
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by Sandeep Krishnan
on February 3, 2014
Zenoss Core has lot of daemons that can be used for various purpose.
While you might not use all of the daemons in your Zenoss environment, it is still essential for you to understand all available zenoss daemons, which you can use to solve a specific enterprise monitoring requirement.
In Zenoss v4 all daemons interact with Mysql and zenhub. By default all the zenoss daemons run in info mode.
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by Luke P. Issac
on January 29, 2014
In certain situations it’s a good option to use Nodejs with MySQL instead of PHP or any other server-side language.
By using Nodejs you can get the advantage of its asynchronous behaviour, which in certain case may increase the performance, and you may not need to migrate an existing MySQL database to some other NoSQL database to gain additional performance.
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by Ramesh Natarajan
on January 28, 2014
If you are a newbie in Linux system administration, or an experienced Linux power user, who does typical sysadmin tasks by yourself on your system, you’ll definitely find few books from this list helpful to add to your library.
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by Sandeep Krishnan
on January 27, 2014
Interrupts are signal that are sent across IRQ (Interrupt Request Line) by a hardware or software.
Interrupts allow devices like keyboard, serial cards and parallel ports to indicate that it needs CPU attention.
Once the CPU receives the Interrupt Request, CPU will temporarily stop execution of running program and invoke a special program called Interrupt Handler or ISR (Interrupt Service Routine).
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by Sanjay Kumar
on January 23, 2014
Port is a terminal command utility which is used to update open source software on Mac OS X.
The port command is bundled as part of MacPorts Framework.
You can install port command either by downloading and installing the binary version for your corresponding Mac OS X, or by downloading the source code and compiling it on your OS X version.
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by Terrence Sun
on January 22, 2014
Handling events appropriately is an important aspect of developing any Android Application.
A listener that is an interface with callback functions is used by Android to do the dispatch of event.
When user triggers an event of one component, OS will check whether there is a user level listener registered for it. If yes, callback function will be called so user program can do action for the event.
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My name is Ramesh Natarajan. I will be posting instruction guides, how-to, troubleshooting tips and tricks on Linux, database, hardware, security and web. My focus is to write articles that will either teach you or help you resolve a problem. Read more about