Explain some more commands in Linux
To know the package install and who is installed
which <package name>
To know who you are (like,. Root or ec2-user)
whoami
Long List cmd:
ls -l or ll
Find operation:
Current directory files display
find -type f (f-file)
Current directory display directories:
find -type d (d- directory)
find / -type f -name passwd
Add user for Login (IAM User):
useradd username
See user login:
cat /etc/passwd
Add group :
groupadd group name
Add user into group:
gpasswd -a <username> <groupname> (a is single user)
gpasswd -m <username>, <username1> <groupname> (m is multiple user)
Softlink (in windows “shortcut”):
ln -s <filename> <short linkname>
Note: original file will be removed, shortlink file also removed.
Hardlink :
ln <filename> <harlinkname>
note : if incase original file is removed. Available in hardlink file full data.
Compress the file:
tar -cvf <directory/filename.tar> <filename>
(cvf: v- verbose)
Change zip formate compress file:
gzip <compress filename>
Uncompress the compressed file:
gunzip <filename .tar.gz>
tar -xvf <compressname.tar>
How to install local system file to linux:
Download file and copy the url link below the filename
wget <paste the link>
yum install <full filename> -y
Total delete from current directory:
rm -rf *
Long list:
ls -l / ll
drwxr-xr-xr-x 2 root root 6 Feb 22 15:56 <directory name>
-rw-r–r– 1 root root 0 Feb 22 15:58 <filename>
For examples
- “d” denotes directory
- “-” denotes file
| rwx -1 | r-x -2 | r-x -3 |
| rw | r– | r– |
Read : (r) – 4
Write : (w) – 2
Execute : (x) – 1
Ex:
Directory: Default permissions for directory (755).
rwe – 4+2+1 = 7
rx- 4+1 = 5
rx – 4+1 = 5
File: default permission for file (644)
rw- 4+2 = 6
r- 4 = 4
r- 4 = 4
chmod 777 <directory name>
[7- root/user, 7- group, 7-others]
chmod 444 <filename>
chown <username> <directory name>
chgrp <group name> <directory name>
chmod 777 <directory name>
chmod 666 <directory name>
chmod 700 <directory name>
chmod 765 <filename>
