BobCHub

[[snippets]]
  description = "! - display all files including hidden"
  command = "ls -a"
  output = "ls -a"

[[snippets]]
  description = "! - display files"
  command = "ls"
  output = "ls -a"

BobCHub

################   Z Shell and OH-MY-ZSH    #####################
	
Step 1: Install Updates, Git, and The Z Shell or zsh 

sudo apt-get update
sudo apt-get install zsh
sudo apt-get install git-core

install zsh
wget https://github.com/robbyrussell/oh-my-zsh/raw/master/tools/install.sh -O - | zsh

BobCHub

CIDR Conversion Table
                                                                                                              
CIDR       Dotted                                                                      Number of Classfull Networks ---------|
prefix     Decimal           Hexidecimal              Inverse                                                                |
length     Netmask            Netmask                 Netmask                                                                |
                                                                                          Binary                             |            Number of Usable IPs
/1	   128.0.0.0	      80 00 00 00	   127.255.255.255	   1000 0000 0000 0000 0000 0000 0000 0000	   128 As	       2,147,483,646	
/2	   192.0.0.0	      C0 00 00 00	    63.255.255.255	   1100 0000 0000 0000 0000 0000 0000 0000	    64 As	       1,073,741,822	
/3	   224.0.0.0	      E0 00 00 00	    31.255.255.255	   1110 0000 0000 0000 0000 0000 0000 000

BobCHub

Decimal - Binary - Octal - Hex – ASCII
 Conversion Chart
Decimal Binary Octal Hex ASCII Decimal Binary Octal Hex ASCII Decimal Binary Octal Hex ASCII  
Dec    Binary  Octal   Hex    ASCII   Dec    Binary    Octal    Hex  ASCII  Dec    Binary    Octal   Hex  ASCII Decimal   Binary   Octal  Hex ASCII 
 0    00000000  000    00      NUL    32    00100000    040     20     SP    64   01000000    100    40    @      96     01100000   140   60    `
 1    00000001  001    01      SOH    33    00100001    041     21     !     65   01000001    101    41    A      97     01100001   141   61    a
 2    00000010  002    02      STX    34    00100010    042     22     “     66   01000010    102    42    B      98     01100010   142   62    b
 3    00000011  003    03      ETX    35    00100011    043     23     #     67   01000011    103    43    C      99     01100011   143   63    c
 4    00000100  004    04      EOT    36    00100100    044     24     $     68   01000100    104    44    D      100    01100100   144   6

BobCHub

Firewall with UFW 

sudo apt-get install ufw -------- Install ufw
sudo Vim /etc/default/ufw ------- Edit UFW configuration
sudo ufw reset ------------------ reset ufw rules
sudo ufw default deny incoming -- To set the defaults
sudo ufw default allow outgoing 
sudo ufw allow https ------------ port 443 -- HTTPS connections, which is what encrypted web servers 
sudo ufw allow ssh -------------- port 22 -- Configure your server to allow incoming SSH connections
sudo ufw allow 22

BobCHub

Port Numbers ---

Description
1	TCP Port Service Multiplexer (TCPMUX)
5	Remote Job Entry (RJE)
7	ECHO
18	Message Send Protocol (MSP)
20	FTP -- Data  -- File Transfer Protocol (FTP): used for uploading and downloading files to and from a server.
21	FTP -- Control -- File Transfer Protocol (FTP): used for uploading and downloading files to and from a server.
22	SSH Remote Login Protocol ****

BobCHub

SSH

ifconfig --------------------------------------------------------------------- Find Address

sudo apt-get install openssh-server -------------------------------------------- Install the openssh-server package
sudo cp /etc/ssh/sshd_config /etc/ssh/sshd_config.factory-defaults ------------- Make a copy of the default SSH configura=on
                                                                                 and rename it as factory default
mkdir /home/username/.ssh ------------------------------------------------------ Created a for generated key will live
mkdir ~/.ssh ------------------------------------------------------------------- Create a directory for generated key will live
sudo chmod a-w /etc/ssh/sshd_config.factory-defaults --------------------------- modify its permissions chmod 700

BobCHub

## -- Initializing a new git repository
		$$ git init

	## -- Useful git log commands
		$$ git log --oneline        ## print short sha in one line
		$$ git log -3               ## show only first 3 commit
		$$ git log --author="John"  ## show commits only by this author


	## -- Cloning a git repository

BobCHub

#Running tmux

tmux can be run from within an terminal window by typing tmux

#Commands

tmux commands are introduced by hitting <CTRL>+b followed by the command.

# Sessions

BobCHub

#!/bin/bash
#####################################################
# Name: Bash CheatSheet for Mac OSX
#####################################################


# 0. Shortcuts.


CTRL+A  # move to beginning of line