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    MkCert -

    Make Certificate
    Man Page
    doc1

    SYNTAX
    mkcert [-]

    SWITCH
    -
    -

    EXAMPLE



    ALSO SEE:

    SUDO -

    SuperUser DO
    Man Page

    SSH -

    Secure Shell, OpenSSH remote login client
    Man Page
    doc1 - Mastering OpenSSH - Linux Journal
    doc2 - How to use SSH - geekforgeek

    SYNTAX
    ssh [-] [username]@[remote_IP]

    SWITCH
    -p port (change default port 22)
    -q quiet mode
    -1 Use protocol version 1 only
    -2 Use protocol version 2 only
    -V Display the version number

    EXAMPLE
    ssh user@192.168.1.5
    ssh -p 2222 username@remote_ip

    Nmap -

    Network Mapper, network exploration tool and security / port scanner
    man page
    doc1 - Nmap Cheat Sheet - geeksforgeeks.org

    SYNTAX
    nmap [Scan Type...] [Options] {target specification}

    SWITCH
    -p ports
    -A perform OS and service detection

    EXAMPLE
    basic nmap ping sweep
    nmap -sP 192.168.2.1-254 | grep -i nmap

    Grep -

    Print lines that match pattern
    man page
    doc1 - Unlocking Grep - linuxjournal.com

    SYNTAX
    grep [OPTION...] PATTERNS [FILE...]

    SWITCH
    -i case insentive
    -A (print the specified N lines after match)

    EXAMPLE
    Display N lines after match
    grep -A 'string' FILENAME

    Find -

    Search the live filesystem for files and directories using different criteria
    man page
    doc1 - Find Command - geeksforgeeks.org

    SYNTAX
    grep [options] starting_point PATTERNS [FILE...] action

    SWITCH
    -type fstype (Specifies the type of file to search for 'fstype'(e.g., f for regular files, d for directories).)
    -delete (Delete all matched files) -maxdepth n (Limits how deep into subdirectories the search goes)
    -group name (Matches files that are owned by the 'name' group)
    -exec command {} \; (Executes a command on each matched file)

    EXAMPLE
    find /path/to/search -type f -name "*.txt"
    sudo find / -type f -name "ports.conf"
    -Delete all matched files
    find /tmp -name “*.tmp” -delete
    -which makes a copy of each matched file
    find /etc -name "*.cfg" -exec cp {} /tmp/{}.bak \;

    Useradd -

    Create A New User
    man page
    doc1 - 15 useradd Examples - TechMint.com

    SYNTAX
    useradd [options] username

    SWITCH
    -u UID
    -g GID
    -G group1,group2,group3
    -U (Create a group with the same name as the user, and add the user to this group)
    -d HOME_DIR
    -M (Do not create home dir)
    -m (Create the user's home directory if it does not exist)
    -s SHELL (/sbin/nologin)
    -N (Do not create a group with the same name as the user)
    -r (Create a system account)
    -c COMMENT

    EXAMPLE
    useradd -U -m -d /var/vmail -s /sbin/nologin -u 2000 vmail
    sudo useradd -M -s /usr/sbin/nologin [username]

    ALSO SEE:
    usermod, userdel, groups, groupmod, groupadd, groupdel

    Usermod -

    Modify a user account
    man page
    doc1 -

    SYNTAX
    usermod [options] LOGIN

    SWITCHES
    -aG GROUP (add/append user to GROUP)
    -d HOME_DIR (new home dir)
    -l NEW_LOGIN (The name of the user will be changed from LOGIN to NEW_LOGIN. Nothing else is changed.) (dont forget to change users home DIR)
    -u UID (change a users UID)
    -s SHELL (change a users default SHELL)

    EXAMPLE
    sudo usermod -a -G groupName userName

    Chown -

    Change owner, change the user and/or group ownership of each given File to a new Owner
    man page
    usage Doc1

    -c Verbosely describe the action for each FILE whose ownership actually changes
    -R Recursively change ownership of directories and their contents

    EXAMPLE
    Assign bob as the owner of "MyFile.txt" file in the Shared directory
    $ sudo chown bob /Users/Shared/MyFile.txt
    Assign bob as the owner, and staff as the group for everything in the "tmp" folder
    $ sudo chown -R bob:staff /Users/Shared/tmp/


    Chmod -

    change file mode bits (access permissions)
    man page
    doc1 -

    SYNTAX
    chmod [OPTION]... MODE[,MODE]... FILE...

    SWITCHES
    -f, --silent Suppress most error messages
    -v, --verbose Output a diagnostic for every file processed
    -c, --changes like verbose but report only when a change is made
    -R, --recursive Change files and directories recursively

    EXAMPLE
    chmod 0755 file
    chmod 0655 file
    chmod 400 file - Read by owner
    chmod 040 file - Read by group
    chmod 004 file - Read by world
    chmod 777 file - Allow everyone to read, write, and execute file

    SCP -

    Secure copy
    man page
    doc1 -

    EXAMPLE
    Copy File from a remote host to local host
    $ scp username@from_host:file.txt /local/directory/

    Copy File from local host to a remote host
    $ scp file.txt username@to_host:/remote/directory/

    Copy DIR from a remote host to local host
    $ scp -r username@from_host:/remote/directory/ /local/directory/

    Copy DIR from local host to a remote host
    $ scp -r /local/directory/ username@to_host:/remote/directory/

    Copy file from remote host to remote host
    $ scp username@from_host:/remote/directory/file.txt username@to_host:/remote/directory/

    Bat -

    def
    Man Page
    doc1

    SYNTAX
    command [-]

    SWITCH
    -
    -

    EXAMPLE



    ALSO SEE: