HTTP Request Method Comparison Table, HTTP Request Method Collection

Linux Command — System Information

Command Code	Comment Description
arch	Displays the processor architecture of the machine (1)
uname -m	Displays the processor architecture of the machine (2)
uname -r	Display the version of the kernel currently in use
dmidecode -q	Display hardware system components - (SMBIOS / DMI)
hdparm -i /dev/hda	List the architectural characteristics of a disk
hdparm -tT /dev/sda	Perform a test read operation on the disk
cat /proc/cpuinfo	Display CPU information
cat /proc/interrupts	Display interrupts
cat /proc/meminfo	Check memory usage
cat /proc/swaps	Display which swaps are being used
cat /proc/version	Display the version of the kernel
cat /proc/net/dev	Display network adapters and statistics
cat /proc/mounts	Display loaded file systems
lspci -tv	List PCI devices
lsusb -tv	Display USB devices
date	Display system date
cal 2007	Display the calendar for the year 2007
date 041217002007.00	Set the date and time - month day hour minute year.second
clock -w	Save the time change to BIOS

Linux Commands — System Shutdown (Shutdown, Restart, and Logout)

Command Code	Comment Description
shutdown -h now	Shutdown the system
init	Shutdown the system
telinit	Shutdown the system
shutdown -h hours:minutes &	Shutdown the system at a scheduled time
shutdown -c	Cancel the scheduled system shutdown
shutdown -r now	Restart
reboot	Restart
logout	Logout

Linux Commands — Files and Directories

Command Code	Comment Description
cd /home	Enter the '/home' directory'
cd ..	Return to the parent directory
cd ../..	Return to the directory two levels up
cd	Enter the user's home directory
cd ~user1	Enter the user's home directory
cd -	Return to the last directory you were in
pwd	Print the working directory
ls	List the contents of a directory
ls -F	List the contents of a directory
ls -l	Display detailed information about files and directories
ls -a	List all files, including hidden ones
ls [-9]	List files and directories that contain numbers in their names
tree	Display the directory tree starting from the root directory
lstree	Display the directory tree starting from the root directory
mkdir dir1	Create a directory named 'dir1'
mkdir dir1 dir2	Create two directories at the same time
mkdir -p /tmp/dir1/dir2	Create a directory tree
rm -f file1	Remove a file named 'file1'
rmdir dir1	Remove a directory named 'dir1'
rm -rf dir1	Remove a directory named 'dir1' and its contents
rm -rf dir1 dir2	Remove two directories and their contents at the same time
mv dir1 new_dir	Rename/move a directory
cp file1 file2	Copy a file
cp dir/* .	Copy all files from a directory to the current working directory
cp -a /tmp/dir1 .	Copy a directory to the current working directory
cp -a dir1 dir2	Copy a directory
ln -s file1 lnk1	Create a symbolic link pointing to a file or directory
ln file1 lnk1	Create a hard link pointing to a file or directory
touch -t 712250000 file1	Change the timestamp of a file or directory - (YYMMDDhhmm)
iconv -l	List known encodings
iconv -f fromEncoding -t toEncoding inputFile > outputFile	Change the encoding of characters
find . -maxdepth 1 -name *.jpg -print -exec convert	Batch resize files in the current directory and send them to the thumbnail directory (requires ImageMagick conversion)

Linux Commands — File Search

Command Code	Explanation
find / -name file1	Search for files and directories starting from the root file system '/'
find / -user user1	Search for files and directories owned by user 'user1'
find /home/user1 -name \*.bin	Search for files ending with '.bin' in the directory '/home/user1'
find /usr/bin -type f -atime +100	Search for executable files that have not been used in the past 100 days
find /usr/bin -type f -mtime -10	Search for files that have been created or modified within the last 10 days
find / -name \*.rpm -exec chmod 755 '{}' \;	Search for files ending with '.rpm' and set their permissions
find / -xdev -name \*.rpm	Search for files ending with '.rpm', ignoring removable devices such as optical drives and flash drives
locate \*.ps	Find files ending with '.ps' - run the 'updatedb' command first
whereis halt	Display the location of a binary, source code, or man page
which halt	Display the full path of a binary or executable file

Linux Commands — Mount a File System

Command Code	Explanation
mount /dev/hda2 /mnt/hda2	Mount a disk called hda2 - Ensure the directory '/mnt/hda2' exists
umount /dev/hda2	Unmount a disk called hda2 - Exit from the mount point '/mnt/hda2' first
fuser -km /mnt/hda2	Force unmount when the device is busy
umount -n /mnt/hda2	Perform the unmount operation without writing to the /etc/mtab file - Very useful when the file is read-only or when the disk is full
mount /dev/fd /mnt/floppy	Mount a floppy disk
mount /dev/cdrom /mnt/cdrom	Mount a CD-ROM or DVD-ROM
mount /dev/hdc /mnt/cdrecorder	Mount a CD-RW or DVD-ROM
mount /dev/hdb /mnt/cdrecorder	Mount a CD-RW or DVD-ROM
mount -o loop file.iso /mnt/cdrom	Mount a file or ISO image file
mount -t vfat /dev/hda5 /mnt/hda5	Mount a Windows FAT32 file system
mount /dev/sda1 /mnt/usbdisk	Mount a USB flash drive or flash memory device
mount -t smbfs -o username=user,password=pass //WinClient/share /mnt/share	Mount a Windows network share

Linux Commands — Disk Space

Command Code	Comment Description
df -h	Display the list of mounted partitions
ls -lSr \|more	Arrange files and directories by size
du -sh dir1	Estimate the disk space used by the directory 'dir1'
du -sk * \| sort -rn	Display the size of files and directories in order of capacity
rpm -q -a --qf '%10{SIZE}t%{NAME}n' \| sort -k1,1n	Display the space used by installed rpm packages in order of size (Fedora, Red Hat-like systems)
dpkg-query -W -f='${Installed-Size;10}t${Package}n' \| sort -k1,1n	Display the space used by installed deb packages in order of size (Ubuntu, Debian-like systems)

Linux Commands — Users and Groups

Command Code	Comment Description
groupadd group_name	Create a new group
groupdel group_name	Delete a group
groupmod -n new_group_name old_group_name	Rename a group
useradd -c "Name Surname" -g admin -d /home/user1 -s /bin/bash user1	Create a user belonging to the "admin" group
useradd user1	Create a new user
userdel -r user1	Delete a user ('-r' to exclude the home directory)
usermod -c "User FTP" -g system -d /ftp/user1 -s /bin/nologin user1	Modify user attributes
passwd	Modify password
passwd user1	Modify a user's password (only allowed for root to execute)
chage -E 202-12-31 user1	Set the expiration date for a user's password
pwck	Check the '/etc/passwd' file format and syntax correction, as well as existing users
grpck	Check the '/etc/passwd' file format and syntax correction, as well as existing groups
newgrp group_name	Log in to a new group to change the default group of newly created files

Linux Commands — File Permissions - Use "+" to set permissions, use "-" to cancel

Command Code	Comment Explanation
ls -lh	Display permissions
ls /tmp \| pr -T5 -W$COLUMNS	Divide the terminal into 5 columns for display
chmod ugo+rwx directory1	Set read (r), write (w), and execute (x) permissions for everyone (u), group (g), and others (o) on a directory
chmod go-rwx directory1	Remove read, write, and execute permissions for the group (g) and others (o) on a directory
chown user1 file1	Change the ownership of a file
chown -R user1 directory1	Change the ownership of a directory and all files within it
chgrp group1 file1	Change the group of a file
chown user1:group1 file1	Change the owner and group of a file
find / -perm -u+s	List all files in the system that use SUID control
chmod u+s /bin/file1	Set the SUID bit for a binary file - the user running the file is given the same permissions as the owner
chmod u-s /bin/file1	Disable the SUID bit for a binary file
chmod g+s /home/public	Set the SGID bit for a directory - similar to SUID, but for directories
chmod g-s /home/public	Disable the SGID bit for a directory
chmod o+t /home/public	Set the STIKY bit for a file - only the legitimate owner can delete the file
chmod o-t /home/public	Disable the STIKY bit for a directory

Linux Commands — Special File Attributes - Use "+" to set permissions, use "-" to cancel

Command Code	Comment Explanation
chattr +a file1	Only allow appending to the file
chattr +c file1	Allow the file to be automatically compressed/decompressed by the kernel
chattr +d file1	During file system backup, the dump utility will ignore this file
chattr +i file1	Set the file to be immutable, cannot be deleted, modified, renamed, or linked
chattr +s file1	Allow a file to be safely deleted
chattr +S file1	Once an application writes to this file, make the system immediately write the modified results to the disk
chattr +u file1	If the file is deleted, the system will allow you to recover the deleted file later
lsattr	Display special attributes

Linux Command — File Packing and Compression

Command Code	Comments
bunzip2 file1.bz2	Unzip a file called 'file1.bz2'
bzip2 file1	Compresses a file called 'file1'
gunzip file1.gz	Unzip a file called 'file1.gz'
gzip file1	Compresses a file called 'file1'
gzip -9 file1	Maximum compression
rar a file1.rar test_file	Create a package called 'file1.rar'
rar a file1.rar file1 file2 dir1	Compresses 'file1', 'file2', and the directory 'dir1' at the same time
rar x file1.rar	Unzip rar package
unrar x file1.rar	Unzip rar package
tar -cvf archive.tar file1	Create an uncompressed tarball
tar -cvf archive.tar file1 file2 dir1	Create an archive file containing 'file1', 'file2', and 'dir1'
tar -tf archive.tar	Display the contents of a package
tar -xvf archive.tar	Release a package
tar -xvf archive.tar -C /tmp	Release the compressed package to the /tmp directory
tar -cvfj archive.tar.bz2 dir1	Create a bzip2 compressed package
tar -jxvf archive.tar.bz2	Unzip a bzip2 compressed package
tar -cvfz archive.tar.gz dir1	Create a gzip compressed package
tar -zxvf archive.tar.gz	Unzip a gzip compressed package
zip file1.zip file1	Create a zip compressed package
zip -r file1.zip file1 file2 dir1	Compresses several files and directories into a zip compressed package at the same time
unzip file1.zip	Unzip a zip compressed package

Linux Commands — RPM Package - (Fedora, Redhat and similar systems)

Command Code	Comment Description
rpm -ivh package.rpm	Install an RPM package
rpm -ivh --nodeeps package.rpm	Install an RPM package ignoring dependency warnings
rpm -U package.rpm	Update an RPM package without altering its configuration files
rpm -F package.rpm	Update a specifically installed RPM package
rpm -e package_name.rpm	Remove an RPM package
rpm -qa	Display all installed RPM packages in the system
rpm -qa \| grep httpd	Display all RPM packages with "httpd" in their names
rpm -qi package_name	Obtain special information about an installed package
rpm -qg "System Environment/Daemons"	Display the RPM package of a component
rpm -ql package_name	Display the list of files provided by an installed RPM package
rpm -qc package_name	Display the list of configuration files provided by an installed RPM package
rpm -q package_name --whatrequires	Display the list of packages that have a dependency on an RPM package
rpm -q package_name --whatprovides	Display the disk space occupied by an RPM package
rpm -q package_name --scripts	Display the scripts executed during installation/deletion
rpm -q package_name --changelog	Display the modification history of an RPM package
rpm -qf /etc/httpd/conf/httpd.conf	Identify which RPM package provides the given file
rpm -qp package.rpm -l	Display the list of files provided by an uninstalled RPM package
rpm --import /media/cdrom/RPM-GPG-KEY	Import a public key digital certificate
rpm --checksig package.rpm	Confirm the integrity of an RPM package
rpm -qa gpg-pubkey	Confirm the integrity of all installed RPM packages
rpm -V package_name	Check file size, permissions, type, owner, group, MD5 checksum, and last modification time
rpm -Va	Check all installed RPM packages in the system - use with caution
rpm -Vp package.rpm	Verify that an RPM package is not yet installed
rpm2cpio package.rpm \| cpio --extract --make-directories bin	Execute executable files from an RPM package
rpm -ivh /usr/src/redhat/RPMS/`arch`/package.rpm	Install a built package from an RPM source
rpmbuild --rebuild package_name.src.rpm	Build an RPM package from RPM source

Linux Commands — YUM Package Manager - (Fedora, RedHat, CentOS, etc.)

Command Code	Comment Description
yum install package_name	Install a package using yum, resolving dependencies automatically
yum update	Update all installed packages to their latest versions
yum update package_name	Update a specific package to its latest version
yum remove package_name	Remove a package and its dependencies that were installed with it
yum list available	List all available packages from repositories
yum search keyword	Search for packages by keyword
yum info package_name	Display detailed information about a package
yum clean all	Clean up cache and metadata to free disk space
yum groupinstall group_name	Install a package group
yum groupremove group_name	Remove a package group
yum check-update	Check for available updates without applying them

Linux Command — YUM Package Upgrader - (Fedora, RedHat and similar systems)

Command Code	Comment Description
yum install package_name	Download and install an rpm package
yum localinstall package_name.rpm	Install an rpm package, using your own software repository to resolve all dependencies
yum update package_name.rpm	Update all installed rpm packages in the current system
yum update package_name	Update an rpm package
yum remove package_name	Delete an rpm package
yum list	List all packages currently installed in the system
yum search package_name	Search for a software package in the rpm repository
yum clean packages	Clean the rpm cache and delete downloaded packages
yum clean headers	Delete all header files
yum clean all	Delete all cached packages and header files

Linux Command — DEB Package (Debian, Ubuntu and similar systems)

Command Code	Comment Explanation
dpkg -i package.deb	Install/Update a deb package
dpkg -r package_name	Remove a deb package from the system
dpkg -l	Display all deb packages that have been installed in the system
dpkg -l \| grep httpd	Display all deb packages that contain the word "httpd"
dpkg -s package_name	Get information about a specific package that has been installed in the system
dpkg -L package_name	Display the list of files provided by an installed deb package in the system
dpkg --contents package.deb	Display the list of files provided by an uninstalled package
dpkg -S /bin/ping	Confirm which deb package provides the given file

Linux Command — APT Software Tool (Debian, Ubuntu and similar systems)

Command Code	Comment Explanation
apt-get install package_name	Install/Update a deb package
apt-cdrom install package_name	Install/Update a deb package from a CD-ROM
apt-get update	Upgrade the software packages in the list
apt-get upgrade	Upgrade all installed software
apt-get remove package_name	Remove a deb package from the system
apt-get check	Confirm that the dependency software repository is correct
apt-get clean	Clean the cache from downloaded software packages
apt-cache search searched-package	Return the names of software packages that contain the search string

Linux Command — View File Contents

Command Code	Comment Explanation
cat file1	View the contents of the file from the first byte in the forward direction
tac file1	View the contents of a file in reverse from the last line
more file1	View the contents of a long file
less file1	Similar to the 'more' command, but it allows reverse operations in the file like forward operations
head -2 file1	View the first two lines of a file
tail -2 file1	View the last two lines of a file
tail -f /var/log/messages	Real-time view of the content being added to a file

Linux Commands — Text Processing

Command Code	Comment Explanation
cat file1 \| command( sed, grep, awk, grep, etc...) > result.txt	Merge the detailed explanation text of a file and write the summary into a new file
cat file1 \| command( sed, grep, awk, grep, etc...) >> result.txt	Merge the detailed explanation text of a file and write the summary into an existing file
grep Aug /var/log/messages	Search for the keyword "Aug" in the file '/var/log/messages'
grep ^Aug /var/log/messages	Find words starting with "Aug" in the file '/var/log/messages'
grep [-9] /var/log/messages	Select all lines in the '/var/log/messages' file that contain numbers
grep Aug -R /var/log/*	Search for the string "Aug" in the directory '/var/log' and subsequent directories
sed 's/stringa1/stringa2/g' example.txt	Replace "string1" with "string2" in the example.txt file
sed '/^$/d' example.txt	Delete all blank lines from the example.txt file
sed '/ *#/d; /^$/d' example.txt From example.txt	Delete all comments and blank lines in the file
echo 'esempio' \| tr '[:lower:]' '[:upper:]'	Merge the content of the upper and lower cells
sed -e '1d' result.txt	Exclude the first line from the file example.txt
sed -n '/stringa1/p'	View lines that only contain the word "string1"
sed -e 's/ *$//' example.txt	Delete the blank characters at the end of each line
sed -e 's/stringa1//g' example.txt	Delete only the word "string1" from the document and keep the rest
sed -n '1,5p;5q' example.txt	View content from the first line to the 5th line
sed -n '5p;5q' example.txt	View the 5th line
sed -e 's/00*//g' example.txt	Replace multiple zeros with a single zero
cat -n file1	Mark the line numbers of the file
cat example.txt \| awk 'NR%2==1'	Delete all even lines in the example.txt file
echo a b c \| awk '{print $1}'	View the first column of a line
echo a b c \| awk '{print $1,$3}'	View the first and third columns of a line
paste file1 file2	Merge the contents of two files or two columns
paste -d '+' file1 file2	Merge the contents of two files or two columns, separated by "+"
sort file1 file2	Sort the contents of two files
sort file1 file2 \| uniq	Extract the union of two files (duplicate lines are kept only once)
sort file1 file2 \| uniq -u	Delete the intersection, leave the other lines
sort file1 file2 \| uniq -d	Extract the intersection of two files (only keep the files that exist in both files)
comm -1 file1 file2	Compare the contents of two files and delete the contents contained in 'file1' only
comm -2 file1 file2	Compare the contents of two files and delete the contents contained in 'file2' only
comm -3 file1 file2	Compare the contents of two files and delete the common parts of both files

Linux Commands — Character Setting and File Format Conversion

Command Code	Comment Description
dos2unix filedos.txt fileunix.txt	Convert the format of a text file from MSDOS to UNIX
unix2dos fileunix.txt filedos.txt	Convert the format of a text file from UNIX to MSDOS
recode ..HTML < page.txt > page.html	Convert a text file to HTML
recode -l \| more	Display all allowed conversion formats

Linux Commands — File System Analysis

Command Code	Comment Description
badblocks -v /dev/hda1	Check for bad blocks on the hda1 disk
fsck /dev/hda1	Repair/Check the integrity of the Linux file system on the hda1 disk
fsck.ext2 /dev/hda1	Repair/Check the integrity of the ext2 file system on the hda1 disk
e2fsck /dev/hda1	Repair/Check the integrity of the ext2 file system on the hda1 disk
e2fsck -j /dev/hda1	Repair/Check the integrity of the ext3 file system on the hda1 disk
fsck.ext3 /dev/hda1	Repair/Check the integrity of the ext3 file system on the hda1 disk
fsck.vfat /dev/hda1	Restore the MBR content from the backup that has been saved to a floppy disk

Linux Command — CD-ROM

Command Code	Comment Description
cdrecord -v gracetime=2 dev=/dev/cdrom -eject blank=fast -force	Erase the content of a rewritable CD
mkisofs /dev/cdrom > cd.iso	Create an ISO image file of a CD on the disk
mkisofs /dev/cdrom \| gzip > cd_iso.gz	Create a compressed ISO image file of a CD on the disk
mkisofs -J -allow-leading-dots -R -V "Label CD" -iso-level 4 -o ./cd.iso data_cd	Create an ISO image file of a directory
cdrecord -v dev=/dev/cdrom cd.iso	Burn an ISO image file
gzip -dc cd_iso.gz \| cdrecord dev=/dev/cdrom -	Burn a compressed ISO image file
mount -o loop cd.iso /mnt/iso	Mount an ISO image file
cd-paranoia -B	Transfer audio tracks from a CD to wav files
cd-paranoia -- "-3"	Transfer audio tracks from a CD to wav files (parameter -3)
cdrecord --scanbus	Scan the bus to identify SCSI channels
dd if=/dev/hdc \| md5sum	Check the md5sum code of a device, such as a CD

Linux Command — Network - (Ethernet and WIFI Wireless)

Command Code	Comment Description
dhclient eth	Enable the 'eth' network device in DHCP mode
ethtool eth	Display traffic statistics of the network card 'eth'
host www.example.com	Find the hostname to resolve the name and IP address and mirror
hostname	Display the hostname
ifconfig eth	Display the configuration of an Ethernet card
ifconfig eth 192.168.1.1 netmask 255.255.255.	Control the IP address
ifconfig eth promisc	Set 'eth' to promiscuous mode to sniff packets (sniffing)
ifdown eth	Disable a 'eth' network device
ifup eth	Enable a 'eth' network device
ip link show	Display the connection status of all network devices
iwconfig eth1	Display the configuration of a wireless network card
iwlist scan	Display wireless networks
mii-tool eth	Display the connection status of 'eth'
netstat -tup	Display all enabled network connections and their PID
netstat -tup1	Display all listening network services and their PIDs
netstat -rn	Display routing table, similar to the "route -n" command
nslookup www.example.com	Resolve hostnames to map names to IP addresses and mirrors
route -n	Display routing table
route add -net 0/0 gw IP_Gateway	Control the default gateway
route add -net 192.168.0.0 netmask 255.255.0.0 gw 192.168.1.1	Control static routing to the network '192.168.0.0/16'
route del 0/0 gw IP_gateway	Delete static route
echo "1"> /proc/sys/net/ipv4/ip_forward	Enable IP forwarding
tcpdump tcp port 80	Display all HTTP loopbacks
whois www.example.com	Lookup in the Whois database

Linux Commands — Microsoft Windows Networking

Command Code	Comment Description
mount -t smbfs -o username=user,password=pass //WinClient/share/mnt/share	Mount a Windows network share
nbtscan ip addr	NetBIOS name resolution
nmblookup -A ip addr	NetBIOS name resolution
smbclient -L ip addr/hostname	Display remote shares from a Windows host
smbget -Rr smb://ip addr/share	Downloads files from a Windows host via SMB, akin to wget

Linux Commands — IPTABLES (Firewall)

Command Code	Comment Description
iptables -t filter -L	Display all chains in the filter table
iptables -t nat -L	Corrected: Display all chains in the nat table
iptables -t filter -F	Flush all rules based on the filter table
iptables -t nat -F	Flush all rules based on the nat table
iptables -t filter -X	Delete all links created by the user
iptables -t filter -A INPUT -p tcp --dport telnet -j ACCEPT	Allow telnet access
iptables -t filter -A OUTPUT -p tcp --dport telnet -j DROP	Block telnet access
iptables -t filter -A FORWARD -p tcp --dport pop3 -j ACCEPT	Allow forwarding of POP3 connections on the link
iptables -t filter -A INPUT -j LOG --log-prefix	Log all packets that are blocked in the link
iptables -t nat -A POSTROUTING -o eth -j MASQUERADE	Set up a PAT (Port Address Translation) on eth to mask outgoing packets
iptables -t nat -A POSTROUTING -d 192.168..1 -p tcp -m tcp --dport 22 -j DNAT --to-destination 10...2:22	Redirect packets sent to a host address to another host

Linux Commands — Monitoring and Debugging

Command Code	Comment Description
free -m	List RAM status in megabytes
kill -9 process id	Forcefully close a process and end it
kill -1 process id	Force a process to reload its configuration
last reboot	Display reboot history
lsmod	List loaded kernel modules
lsof -p process id	List a file list opened by a process
lsof /home/user1	List the list of files opened in the given system path
ps -eafw	List Linux tasks
ps -e -o pid,args --forest	List Linux tasks in a hierarchical manner
pstress	Display programs in a tree diagram
smartctl -A /dev/hda	Monitor the reliability of a hard disk device by enabling SMART
smartctl -i /dev/hda	Check whether the SMART of a hard disk device is enabled
strace -c ls >/dev/null	List system calls made and receive them with a process
strace -f -e open ls >/dev/null	List library calls
tail /var/log/dmesg	Display internal events during the kernel boot process
tail /val/log/messages	Display system events
top	List Linux tasks that use the most CPU resources
watch -nl ‘cat /proc/interrupts’	List real-time interrupts

Linux Commands — Other Common Commands

Command Code	Comment Description
alias hh='history'	Set an alias for the history command
apropos ...keyword	List a command list including the program keyword, especially useful when you only know what the program does and do not remember the command
chsh	Change the shell command
chsh --list-shells	A good command to know if you need to remotely connect to another machine
gpg -c filel	Encrypt a file with GNU Privacy Guard
gpg filel.gpg	Decrypt a file with GNU Privacy Guard

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