Category: Linux Administration

Creating Local Yum Repository on RED HAT or CentOS

Lets look at the steps required to setup local yum repository. We will create local repo called demolocal. We will then copy single package iperf3-3.0.11-1.fc22.x86_64.rpm as an example and install it from our demolocal repo.

Linux job scheduling with crontab

We previously looked into scheduling jobs with at command now we will look into using crontab to execute commands in the future time.

Linux job scheduling with at

Being able to execute a Linux command at a later time is very important feature for systems Administrator. Job scheduling is taken care by two daemons: atd and crond. Atd manages jobs that run only ones while crond runs jobs at predefined times.

Soft vs Hard links Linux

In order to better understand soft and hard links lets take a quick look at inode and what it does. Inode basically is metadata that holds files information in form of attributes like type, size, permissions, owners name, last access time, modification time, ACL settings. Inode also has pointers to the location in the file

Using Linux Find Command

Lets take a look at few examples using Linux powerful find command. In general find command recursively searches directories and finds files that match specific criteria. This powerful tool can look for files based on name, inode number, modification time, file types and even size. Find command can also perform some action on found files.

Linux File and Directory Attributes

Certain attributes can be set on Linux file and directory helping us control what can and cannot be done on it. Attributes can protect files and directory from being deleted, modified, compressed or updated by any user including root.

Linux Compression and Archiving Tools

Compression tools are used to compress one or more files. Archiving tools  collect files and their metadata together to produces one file. We will look at basic usage of following compression and archiving tolls. gzip and gunzip (can achieve better compression compared to ZIP) bzip2 and bunzip2 tar (archiving) zip and unzip (capable of archiving