Installing software packages on HPUX can be little painful when it has lot of dependencies. depothelper utility will help you to download and install the software packages and all it’s dependencies automatically.
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If your server has two HBA cards connected to EMC SAN storage device, you can implement load-balancing, and fail-over on the HBA cards using the EMC PowerPath software.
Powermt management utility helps you manage I/O paths from the server to the EMC storage device. In this article, let us discuss how to use powermt command with practical examples.
Programmers should handle all kinds of errors to protect the program from failure.
In C programming language, there is no direct support for error handling. You have to detect the failure and handle the error. In C programming language, return values represents success or failure. Inside a C program, when a function fails, you should handle the errors accordingly, or at least record the errors in a log file.
When you are running some program on Linux environment, you might notice that it gives some error number. For example, “Error no is : 17”, which doesn’t really say much. You really need to know what error number 17 means.
This article shows all available error numbers along with it descriptions. This article might be a handy reference for you, when you encounter an error number and you would like to know what it means.
Using NFS (Network File System), you can mount a disk partition of a remote machine as if it is a local disk. This article explains how to export a file system to a remote machine and mount it both temporarily and permanently.
Expect scripting language is used to feed input automatically to an interactive program. It is easy to learn compared to other scripting languages. Using expect script sysadmins and developers can automate redundant tasks easily. It works by expecting specific strings, and sending or responding strings accordingly.
Following three expect commands are used when automating any interactive processes.
- send – to send the strings to the process
- expect – wait for the specific string from the process
- spawn – to start the command
Data loss will be costly. At the very least, critical data loss will have a financial impact on companies of all sizes. In some cases, it can cost your job. I’ve seen cases where sysadmins learned this in the hard way.
There are several ways to backup a Linux system, including rsync and rsnapshot that we discussed a while back.
This article provides 6 practical examples on using dd command to backup the Linux system. dd is a powerful UNIX utility, which is used by the Linux kernel makefiles to make boot images. It can also be used to copy data. Only superuser can execute dd command.
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Question: I have created triggers in Oracle database. But, I’m new to PostgreSQL. Can you explain me how to create a trigger in Postgres with proper examples?
Answer: A trigger can be used to execute a function when an event (insert, or delete, or update) occurs in a table. Let us review how to create a trigger with an example.
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There are two types of links available in Linux — Soft Link and Hard Link.
Linux ln command is used to create either soft or hard links.
This article explains how to create soft link, how to create hard link, and various link tips and tricks with 10 practical examples.
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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