How to install locate command in Linux Redhat and Centos

To install the locate command (mlocate) in Redhat or Centos, use the ’YUM’ command, install function. 

  • Logon as ‘root’ or use with ‘sudo’ permissions
  • Then, run a ’man’ command to confirm that the locate command is not already installed: ‘man locate’

Example ‘man’ command (as root user)

[root@blog-server ~]# man locate

  • If the ’man’ documentation page returns, then it is already installed.  If no ’man’ documentation page is returned, then run the ‘yum install’ command.
  • Run the ‘yum install’ command as ‘root’ or ‘sudo’ user:

Example ‘yum install’ command (as root user)

[root@blog-server ~]# yum install mlocate

Example ‘yum install’ command (as sudo user)

[root@blog-server ~]# sudo yum install mlocate

Then run the [root@data-server ~]# updated

Example Run ‘updatedb’ Command (as Root user)

[root@blog-server ~]# updated

Example Run ‘updatedb’ Command (as sudo user)

[root@blog-server ~]# sudo updatedb

How To quit the Linux vi editor without saving changes

To quit the Linux ’vi’ editor without saving any changes which have been made:

To Exit the insert or append mode

  1. From within insert or append mode, press the ‘Esc‘ key.

To Enable VI Command Line

  1. Press the ‘:’ (colon) Key. The cursor should reappear in the lower-left corner of the screen beside a colon prompt.
  2. Then, Enter the ‘q!’ Command and press the ‘Enter’ Key.

Example VI Command Line

: q!

This will quit the Linux VI editor, and all changes the document made in this session will be lost.

Linux Move (mv) Command

The Linux move command (mv) is one of the essential commands, which can be very useful in Linux, Unix, and AIX.  The primary purpose of the move command is obviously to move files, and of course, directories.   The move command may also be used to rename files and to make backups.

Move Command Syntax

$ mv [options] source (file or directory)  destination

Move Command options

option description
mv -f force move by overwriting destination file without prompt
mv -i interactive prompt before overwriting
mv -u update – move when the source is newer than the destination
mv -v verbose – print source and destination files
MV – t explicitly saying to move the file or directory here, rather trying to fit everything into the last argument.
mv * Move all (Multiple) files to a specific director without listing by name

For More move command details see the Linux documentation manuals using the man command

$ man mv

mv command examples

Here are some quick and very simple move command (MV) examples for reference.

Move Move to files  to the /Archive/ directory:

$ mv happy.txt garden.txt /Archive/

Move all “.txt” files in the current directory to subdirectory backup:

$ mv *.txt backup

Move all files in subdirectory ‘backup’ to current directory:

$ mv backup/*

Rename file happy.txt to happy.bak filename:

$ mv happy.txt happy.bak

Rename directory backup to backup2:

$ mv backup backup2

Update – move when happy.txt is newer or missing in target directory:

$ mv -u happy.txt backup

Move happy.txt and prompt before overwrite backup / happy.txt:

$ mv -v happy.txt backup

The most Important Linux Distributions To Learn Professionally

Many of us either want a way to import our Linux knowledge, improve our technical career options or perhaps, move into the technology career.  To do any of these efficiently them, the first step would be to focus on the major Linux distribution used by employers. 

The most adapted distributions Linux are Red Hat Enterprise Linux (RHEL) and Ubuntu, so, of the multitude of Linux distributions available, these would be the to learn if you want to move your career forward.

However, if you are seeking an inexpensive alternative to hone your Linux skills at home, then CentOS, is likely your best choice since it is free and is pretty much a copy of RedHat.

Related References

Linux – What is yum?

Linux
Linux

In simple terms, yum is a, command-line interface, package manager utility for computers running the Linux operating system, which augments the RPM Package Manager capabilities. yum is the primary tool for getting, installing, deleting, querying, and managing RPM software packages. Also, yum is used in Red Hat Enterprise Linux (RHEL) versions 5 and later.

Linux – how to display file system disk space statistics

Linux
Linux

In Linux there are lot of ways to disk size and/or space, but the ‘Disk Filesystem’ (df) command is old reliable and has been around a long time.   The ‘df’ command provides a summary of disk space and free space, which I find myself coming back to time after time.

Basic Command Format

DF -<<Option>>   <<File>>

Example ‘Disk Filesystem’, Command

df -h

  • -h = Human readable in MegaBytes

For more details in Linux

df –help

Example Command Output

root@BlogSrvr1 /]# df -h

Filesystem            Size  Used Avail Use% Mounted on

/dev/mapper/vg_BlogSrvr1-lv_root

36G   34G   16M 100% /

tmpfs                 3.9G     0  3.9G   0% /dev/shm

/dev/sda1             477M   33M  419M   8% /boot

/dev/mapper/vg_BlogSrvr1-LogVol03

11G   27M  9.9G   1% /data

/dev/mapper/vg_BloSrvr1-lv_home

4.8G   33M  4.6G   1% /home

/dev/mapper/vg_BlogSrvr1-LogVol04

25G   13G   11G  55% /opt/IBM

/dev/mapper/vg_BlogSrvr1-LogVol05

11G  6.0G  3.7G  62% /scratch

/dev/mapper/vg_BlogSrvr1-LogVol06

11G   27M  9.9G   1% /tmp/dev/shm

Linux – How to compress an entire directory

Linux
Linux

From time to time there is a need to package up a folder for any number of reasons which may include things like:

  • Migration
  • Movement to a new location
  • Movement to a new server
  • To keep a backup
  • Or simply to save space

Compressing a folder is folder can be very useful, but for those of us who don’t do it all the time, it is nice to have a pattern to follow.  Also, even an experienced user can get brain cramp, if they have not had a reason to compress a folder in a while. So, here is a simple pattern to follow to compress a folder and its contents.

Basic Command Format

tar -zcvf <<archive-name>>.tar.gz <<directory-name>>

Example Compress Command

tar -zcvf  blog_files_backup.tar.gz   sqlfiles

Linux tar command line options used here

  • -z = Compress archive using gzip program
  • -c = Create archive
  • -v = Verbose i.e display progress while creating archive
  • -f = Archive File name

For help with the tar command in Linux

To get additional detail on the tar command in Linux, just need to type:

 tar -?