Crontab command manages the cron table that is used by the cron daemon to execute the cron jobs. This article explains the various command line options of the crontab command.
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Linux
I’ve compiled 25 performance monitoring and debugging tools that will be helpful when you are working on Linux environment. This list is not comprehensive or authoritative by any means.
However this list has enough tools for you to play around and pick the one that is suitable your specific debugging and monitoring scenario.
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NIS stands for Network Information Service.
NIS is also called as YP. YP stands for Yellow Pages.
NIS is a lookup service for set of databases. The databases in this cases can be a passwd file, group file, hosts file, etc. This is primarily used as a central repository to hold all username and passwords (i.e /etc/passwd), and different servers can authenticate against this server for the username and password.
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Strace is a debugging tool that will help you troubleshoot issues.
Strace monitors the system calls and signals of a specific program. It is helpful when you do not have the source code and would like to debug the execution of a program. strace provides you the execution sequence of a binary from start to end.
This article explains 7 strace examples to get you started.
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This article is part of our on-going performance monitoring series of articles.
In this article, let us focus on how to monitor network traffic and log them for later analysis using vnstat utility.
vnstat is a command line utility that displays and logs network traffic of the interfaces on your systems. This depends on the network statistics provided by the kernel. So, vnstat doesn’t add any additional load to your system for monitoring and logging the network traffic.
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During performance testing of your application you might want to perform some sort of memory regression testing. This article contains two memory regression scripts that are written in perl which will occupy a specific amount of memory for a certain amount of time, for your testing.
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Have you ever wondered how your computer talks to other computers on your local LAN or to other systems on the internet?
Understanding the intricacies of how computers interact is an important part of networking and is of equal interest to a sysadmin as well as to a developer. In this article, we will make an attempt to discuss the concept of communication from the very basic fundamental level that needs to be understood by everybody.
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Question: Can you explain how to use OR, AND and NOT operators in Unix grep command with some examples?
Answer: In grep, we have options equivalent to OR and NOT operators. There is no grep AND opearator. But, you can simulate AND using patterns. The examples mentioned below will help you to understand how to use OR, AND and NOT in Linux grep command.
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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